New here, thought I would participate.
In general, I have only had one really "bad" night on piperazines, but I think my fun has more to do with set and setting than the actual drug. If I'm convinced I'm going to have a good time, I will have a good time, even if I feel like I'm going to die in the morning.
BZP, like many have said before, is very stimulant-like. Come-up takes about an hour for me, but it doesn't creep up--it kind of smacks me all at once. I didn't really get a "euphoria" from it, I just couldn't sit still or keep focused on anything for more than a few seconds. I felt like talking, but everything that came out of my mouth made absolutely no sense, and I would confuse myself. The effects do come in waves of intensity, where a few minutes it's REALLY intense, and then it's not-so-intense but you still know you're under the influence of something (sort of like MDMA, I guess... I haven't really taken any other amphetamines before, so I'm not sure what to compare it to.) I think, honestly, that's the only way to compare it to "rolling", but again... that may just be me. Other than that, I don't see any similarity between MDMA and BZP.
The comedown is pretty harsh. Sleep is out of the question and the dry-mouth makes eating impossible (and that's assuming you have any appetite!) These go away about 24 hours after taking the drug for me, and when I'm finally able to sleep, I have to fight for it. I feel really stupid for days after taking it. Short term-memory problems persist for about a week. I also get really paranoid, but that could also just be from sleep deprivation.
Then again... two of the people I took BZP with had no problems sleeping or eating. They actually passed out 6 hours after taking it. They did smoke a lot of weed and drink a lot of alcohol throughout the night, though.
mCPP is a lot more "trippy", but not really in the classic psychedelic sense. It's a really
CREEPY trip, that's the only way I can describe it. Everything you see/hear/experience has a very eerie vibe. I get mild hallucinations, some auditory hallucinations (although, I have these while sober.) My mind goes in a million directions when I'm on it, but not in the speedy way that BZP produces. Music is... I don't know. Weird. Interesting, but not always enjoyable. It definitely doesn't sound "right". The last time I had this, I was listening to a song, and my friend turned on a strobe light. The music started skipping in sync with the strobing... it was kind of cool, but at the time, it was creepy to me.
The come-up is about 45 minutes to an hour for me. This one sneaks up on me. I'll think I'm sober still, and then I'll go to do a simple task, and my mind sslloowwllyy wanders off... then I snap back to reality for a moment and realize that it's kicking in. It's really harsh on my stomach, so I have to force myself to not throw up. Like people have said, it does make a lot of people violently ill.
In my experience, mCPP has a weird body buzz that comes and goes in waves (again, this is probably where the uninformed confuse it with MDMA.) The body buzz isn't always pleasant, though. Sometimes it can feel almost like an orgasm, but the very next wave feels like pins and needles.
Another peculiar thing about mCPP: taste. During one of the body buzz waves, things taste pretty normal (drinks, candy, etc.) When you're not in the middle of one of those, EVERYTHING tastes like salt. Just salt. Nothing tastes sweet, sour... JUST SALT. Again... kind of creepy.
The come-down is a bit harsh, but not as bad as BZP. Sleep is really difficult for me, but my best friend has no problem. My mind becomes really suspicious of itself. I get extremely anxious and paranoid, and I get confused really easily. I feel like I'm still tripping, but I'm not. It's sort of similar to a freak-out from smoking too much weed. This feeling subsides over the course of a week. It also dehydrates the hell out of me. Even if I drink water and gatorade all night, I always feel like I need an IV saline drip in the morning.
The only time I had a bad night on a piperazine was from mCPP, but the reason for it was the conversation my friends and I were having at the time turned very inappropriate, and it really scared the hell out of me. I don't even know how it began, but in my head, I was convinced for a few moments that my best friend had molested my daughter (yeah... talk about a bad trip.) I couldn't shake that feeling and I spent the rest of the night scared for my daughter's life and mine.
mCPP takes me to a really dark, disturbing place. Except for the above, I'm a perverse enough individual that I kind of enjoy that place. Of course, nothing beats the best substance ever created by humans: MDMA

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