I will just contribute to the thread from a very different perspective maybe but with a similar observation about the treacherous feel of 3FPM. For personal but also pretty much the same basic reasons : extremely addictive and, in my opinion, fucks with your head. I do not need what others will probably call "nice or mild euphoria".
(btw english is not my native language)
Been clean from pretty much everything for about a year but I found a job and had a hard time adjusting to it. So last few months I've been using MPA, almost daily, taking two or three moderate doses per day. It helps a lot with my work, no complications at all. I have been active, productive, talkative, not forgetful, and most of all clear-thinking. So basically the same guy, just not as tired as I should or could be. That's what I need from a stimulant nowadays and my opinion on 3FPM is solely based on its ability to give you some "buzz"
AND yet keep you a functional human being, at work.
MPA even with the vasoconstriction and the difficulty to fall asleep is more suitable for my needs : a clear-headed physical stimulation that lasts long enough to keep the doses more or less sparse. I can't afford myself to go on a binge or even make my free-time drinking longer, so taking a form of "speed" that doesn't encourage me in those things is appreciable. Overall I never used speed, or whatever was in those shitty bags that i used to buy, for "fun" anyway.
The issue for me about MPA was that some nights were too short because of it, "forcing" me to restart the cycle in the morning... And since it most definitely hurts the heart, I wanted to try 3FPM. I did, and it's not what I need.
I waited a leave from work to try it and ended up using the 3g that I had in a few days because, honestly, it is quite pleasant but not functional at all. Well, sure I took some pleasure in writing a few very long and pertinent/inspired emails/PM to coworkers and friends. The problem is that I kept redosing constantly and getting "lost" in various activities for hours. Nothing productive came out of it. For example I didn't clean my place like I wanted to, kept forgetting, maybe cause it's not "fun"... Well even on MPA I do it anyway. On MPA at least I try to go to sleep early, work or not and I enjoy various activities with or without it and it doens't fuck with my priorities.
On 3FPM I ended up taking a few benzos here and there to get some sleep but not because I'm a reasonable person, because I didn't want to "waste" the remaining lines... And when I say "lines" I only speak for the first day cause this thing hurts like hell, but I kept bombing it... I feel like I mostly wasted my time and my money just to be slightly excited for no fucking reason, other than the next dose, and chasing a greater high that never actually came... That's exactly the "mood" that I hate and fear, cause frankly, I'm prone to it. It made me slightly delusional, kinda like when a few glasses can very subtly make you say or do stupid shit, like for example take another one... That's how I would describe the effects of 3FPM on me : slightly euphoric and energetic, unseemingly loosing lucidity, loosing track of time (appetite suppression helps greatly in that department) and in the end just wasting time between the doses.
I just can't use it. It's not for me. For work, like alcohol or weed, it would be a disaster. And for fun it's actually not that strong, at least not worth it imo.
After months of using MPA, I could stop (almost) whenever I wanted, and I did the times that I needed to, for example on the week-ends. With MPA the rules are simple, it's bad for the heart, it tends to keep me agitated longer than I need but it never made me lose myself in it, or lose focus on my work, at least so far. I use it "carefully", knowing that it's a fucked up habit to have anyway, and I consider that I get what I pay for out of it. I use it almost like coffee, even though of course, I know, I shouldn't, but at least I know that I am less likely to abuse it, I mean use it against my better judgement.
3FPM it's fun, it feels nice, the veins and the heart feel fine, I even can drink a few beers... again and again and again. Mood-lifting and at the same time not powerful enough cause I kept redosing to get a better high... It's probably my fault but 3FPM felt so "forgiving" and "easy-going" that I could abuse it way more than MPA. Like I said MPA doesn't affect my mood as much, which for me is a good thing. I get some "sober" fun, cause it makes me talkative, but at the same time I have the energy AND the lucidity to do the shit that needs to be done. Also, unlike 3FPM, it doesn't disturb my appetite, and it "forces" me to drink healthy amounts of water...
Although MPA seems way more harmful for the cardiac system, probably the kidneys also, it leaves my head clearer and I "enjoy" it more. 3FPM is maybe closer to real "speed" or antidepressants, hence maybe the "manic" feel that I had. I'm just easily tired and easily irritated because of that, otherwise my mood is fine, or fucked up enough already, so I don't need to treat that "symptom", if I get only the physical energy that I lack, without the bullshitty "happiness", I'm good. Although I'm sure MPA can and will fuck me up in a different way, I do prefer it to 3FPM.