Hey Ektor, sorry I didn't get a chance to find your post before you had to take the plunge in the dark.
Essentially I came to most of the conclusions you've come to, and I think you worded it quite well. For me it totally eliminates the comedown/crash/cravings. As for the high, I agree that it definitely changes the "character" of the high, although after dozens of trials I still can't quite say if it's for the better or worse .. it's just, different.
I've even successfully used Piracetam to get rid of the icky feelings I get from doing coke all night when nothing else was working
tl;dr
Piracetam rocks. I've tried it with almost every drug available. Generally I've found it doesn't synergize well; actually Piracetam leaves me feeling so good I don't feel the desire to do other drugs. When I do combine it with other substances, I usually feel I need more of that drug to achieve the same high, but also that I don't experience a comedown or negative side-effects.
I started taking Piracetam some time ago. It took about 2-3 weeks for me to feel anything from it at all (and yes, I was trying the 'attack dosage' strategy of starting off with doses as high as 10-20 grams...and still nothing for weeks). That's when the magic happened

Tragically after about 18 months to 2 years that magic started to fade. I began increasing my dose (actually stopped weighing it altogether and started shoveling down as much as I could physically handle at a time) but to no effect, and eventually just stopped bothering to take it. I crashed into a deep depression and mental fog, but didn't really know what to do about it, so after a brief try at alcoholism I eventually just moved back in with my parents and did nothing but sleep and play music until finding another job
Two things I found interesting about the 'racetams: Right around the time I noticed Piracetam wasn't working as well as it used to, I began experimenting with analogues such as Oxiracetam and Aniracetam, and found they instantly made me feel the way Piracetam did when it first started working (you may ask why I didn't just start taking different racetams, and that basically came down to $$$).
The other note of curiosity is, since then I've experimented with going back on Piracetam a few times here and there when I could scrape together enough extra cash for a good supply of it. Now, as I mentioned, the first time I ever started taking it I didn't notice a thing for the first couple weeks or so. However, every time I've taken it since going off of it, I noticed it instantly. I would expect something ingested orally to take at least 20 minutes to an hour to kick in, but this was like, I'd barely get done swallowing it and I'd already be feeling tingly and euphoric all over my body.
As for how it affected my drug use .. it actually caused an almost total cessation. Most drugs just seemed pointless and I felt just fine without them, so why bother? But, I am the kind of guy who, if I'm at a party and someone passes around a bowl or busts out a fat sack of blow and starts chopping lines for everyone in the room, I'm not going to say no....
At the time I was not into downers at all. I had no pain or anxiety or insomnia in my life to speak of, and felt very little euphoria off abusing opiates/benzos/etc. Still, however, if friends were giving them out for free, I'd eat them (or shoot them up). But whereas before I'd say I 'felt little euphoria', with Piracetam I just didn't feel anything at all.
Alcohol was the same deal: it really wasn't my drug of choice, but if I was hanging out with my buddies who did drink I'd be right there with them. Piracetam totally killed that. I couldn't get buzzed or drunk for the life of me and after a drink or two I'd already start feeling sick.
I do **love** dissociatives however, and PIRACETAM MAKES KETAMINE TOTALLY NOT WORK AT ALL!!!

Yes, that is my sadness, anger and confusion all coming out at once. Not just ketamine either..whippits, DXM, anything that is an NMDA antagonist, just completely stopped working. It actually got to the point where I started planning my bipolar episodes and seasonal depression around my drug regimen. I figured during the summer months I would do Piracetam so I could function and make it to work and pay bills and socialize, save up my money and just forget about dissociative tripping for half the year. Then in the winter months I'd wait the few weeks for the last of the Piracetam to wash out of my system and start hitting the k-holes hard. It sucked ass because on days I wasn't doing K or other dissociatives I would be cripplingly depressed, but no one I know really does shit in the winter anyway so I figured I wasn't missing out on much.
Okay, finally getting to the point you were asking about.
I found that Piracetam combined with coke in pretty much the same way it mixes with speed, ecstasy, LSD, 2C-B and other psychedelics and/or stimulants. The high was certainly different. Sometimes I liked it better, sometimes I felt like Piracetam had cheated me out of my buzz. Overall it was about 50/50 and still to this day it's tricky to say.
There was definitely no comedown though (and no anxiety or overstimulation while on the drug, just as there were no cravings later). And yes, even off the cleanest acid or 2c-b I've ever had, if I spend all night running around or dancing without eating food or sleeping I generally feel kind of like shit the next day. Off of super-intense trips sometimes it takes me the whole next day or two to really tune into reality and get grounded in my body again. With Piracetam none of this was an issue (in fact, I don't think I ever 'left' my body or got fully immersed in the trip reality in the first place, which is probably where that vague sense of "I'm not getting as high as I'm used to" was coming from).
Piracetam *definitely* increased the richness of my trips. The typical feeling I get after a good trip is that I learned a lot, grew as a person, especially spiritually, and that I got a lot accomplished as far as my life purpose is concerned. When I would take psychedelics with Piracetam though, I would spend the entire night not really knowing if I was tripping or not...feeling like I hadn't taken enough...disappointed even .... then I would wake up the next day and feel like I'd gotten the benefits of like 10 trips in a row. It was so rewarding and worth it I kept doing it again and again even though I wouldn't feel much of anything until the next morning. I eventually just upped my dose and everything was fine; instead of taking 2-3 hits of acid for a fun night out I would take 6 or 7. Problem solved.
Oh, another thing I've never fully understood: Piracetam + mushrooms never really worked out for me. Instead of tripping I'd just get really sick and felt like I was doing something "wrong". DMT + Piracetam however proved to be a freaking *amazing* combo. Like I said, I don't get that at all...
Sadly I can't really say I ever experienced much of anything rich or spiritually rewarding or personally developing off of cocaine (well, a few times it did give me great insight into how to write music, but other than that it's only been good for sheer hedonistic pleasure).
So I can't exactly say I've ever woke up from a cocaine bender and thought to myself "man, I learned sooo much last night!" But I can say that with Piracetam I've woke up from said bender and thought "man, that was so awesome, and the sex felt sooo good, and..*scratches head* I curiously don't feel like shit at all, in fact, I feel great!"
Ironically Piracetam may have actually led to a temporary *increase* in my coke consumption. Perhaps the only reason I never got that into coke in the first place is that it left me feeling like such total shit (that and I don't find the high that great and it is pretty expensive as far as available drugs go). It eventually got to the point where I wouldn't even do it if it was free just because I didn't feel like being high for 5-20 minutes, trying all night in vain to recapture that high, and feeling like crap the whole next day. You couldn't pay me to do cocaine.
But with Piracetam, once I noticed the comedown and feeling like shit just wasn't there anymore, I loosened up a little bit and started doing blow when it was presented to me at parties. Simply because, I really had no good reason to do it, but I no longer had any reason *not* to do it either, and it was there.
One last anecdote I find funny. One time I actually used Piracetam specifically to eliminate the coke comedown. I wasn't on Piracetam at the time, but I had a bunch in my room (either left over from the previous time I was using it or waiting for a good time to start using it again, idk .. it's rare, but every now and then I have drugs that I'm not using, lol).
So during this time I went out and ended up doing cocaine the whole night. Can't even remember why or with whom, but probably the typical story of, I was bored, my stoner friends invited me over, when I got there they had no weed but just spent their paychecks on blow and were bent on getting everyone in the inner circle as high as they could. I think they needed someone to drive them to get it and I was the only one with a car. Doesn't matter.
So sunrise comes and the coke is all gone and I decide to drive home. I'm lying there in my bed for what seemed like hours, totally unable to sleep or stop chewing the insides of my cheeks to pieces, don't have any weed or benzos or even alcohol in the house, and feeling just wrecked, like whole body aches. I'm sure if you've ever done coke all night you know what I'm talking about and I don't have to describe it any further.
Then the idea came to me about the Piracetam. I remembered how when I was on it I didn't get a comedown. It was a long shot, but I was willing to try anything.
It worked immediately and worked miracles. Within (what seemed like) a few minutes my anxiety was gone, my body and brain stopped hurting, my thoughts stopped racing out of control and settled down to normal. Then I realized I was tired from being up all night and simply went to bed.
Piracetam is like a miracle drug. From a baseline state of mind it seems to pick me up and give me the energy I need to make it through the day. But unlike most stimulating substances, if I happen to be feeling overstimulated from something, Piracetam actually calms me down and even lets me sleep. Weird. And totally awesome!!