I agree with Murple about the research chemicals.
I believe their popularity is due almost entirely to the hype and the fact that they're "new" and "exotic".
Most of them have horrible body loads. It makes absolutely no sense to me why people are willing to make themselves suffer excruciating nausea and just an overall bad physical feeling just to trip or whatever. There are a number of drugs that produce similar effects without having to go through so much trouble. Most of them also lack the depth of LSD or psilocybe mushrooms. Rather the trips are pure physical and abscent of spirituality or the mind-expanding effect.
In my opinion, 5-MeO-DiPT was especially similar to LSD, only second rate. It almost always gave me a stomach ache. Even at high doses, visually it just didn't do a lot. It lacked any marvelous visual hallucinations. It lacked any deep psychological effects. As far as I'm concerned, an sensual effects are purely placebo. I never had sex on it, but masturbating was no different than it would be on any other psychedelic. The coolest thing about it was listening to trippy CD's with vocals. But that definantly didn't make it worthwhile.
AMT produced spectacular hallucinations. But it was the most foulest smelling/tasting chemicals I've ever come across. The two times I tried it, I was burping and the taste/smell kept coming back, which was really disturbing and took away from the experience. Physically, I felt strange both times. The first time I only took 20mgs, so it didn't do very much. The second time I took 40mgs. It made several friends who took the same dose sick. I didn't get sick. And the trip was great... Until I started to come down. At which point I not only was entirely restless, but I was twitching. My friends reported the same thing. It was just mild twitching.. but really really powerful twitches. Quite a disturbing phenomenon. And all of us had some of the most horrible hangovers we have ever felt from any drug the next day. Enough to make me NEVER even want to consider using it again. The only guy I knew who wanted to do it again was someone who also enjoyed high doses of dramamine.
BZP alone didn't do very much as far as a stimulant. It was mild. It made me feel strange physically. A really strong chemical feel. I think the most prominent thing it did was dilate my pupils. Something about it just gave me the feeling that it wasn't healthy. I would assume just drink a large cup of Starbucks coffee instead.
BZP and TFMPP together was a lackluster experience. It felt alright, but it also felt as if it should have been doing more. And of course, it produced one of the most disgusting hangovers ever.
Salvia just felt like a cross between ketamine and ether.
Amanitas were just awful. I got blurred vision. Couldn't see anything far away. Had extreme hot and cold flashes. And ended up having my body drenched in sweat.
The only ones I enjoyed were 5-MeO-DMT and 2C-T-2.
5-MeO-DMT was the only one that produced absolutely no body load or ill feelings at all. It totally agreed with my body. And an hour after initially using it, it seemed to slightly elevate my mood. I assume that one of it's metabolites is serotonin, or a metabolite is metabolized into serotonin. The experiences always felt worthwhile.
2C-T-2 did infact produce a body load. I took 21mgs orally the first time. I definantly did not feel that it was worth it. The body load was significant. But the overall experience was rather weak. However, insufflated it was just absolutely extraordinary. I took some trial and error to figure out an appropriate dose. The first time I tried snorting it, I took 10mgs. Way too much. I vomitted and the first hour my muscles were all severely cramped. However, after that first hour, the ill feelings mostly subsided. The experience was just incredible. Visually, everything was just utterly distorted. Nothing stayed still. I put on some headphones and listened to Thee-O's Alien Abduction psytrance mixtape. After closing my eyes, I experienced synaethasia on a whole new level. Not only did I see the music, but I became bodiless and floated through a universe of colorful sound. It was one of the most amazing trips I've ever had. Eventually I found that the appropriate dose was about 5mgs. It produced only a minimal body load with a +3 trip. And the hallucinations were not all that much less than with 8 or 10mgs. The other thing that was interesting is that I could think very clearly on 2C-T-2. Combining it with MDMA was also amazing.
The only other ones that seem worthwhile to me are 2C-I and 4-AcO-DET. 2C-I seems as if the body load is bareable and the overall experience is pleasant. And being that 4-AcO-DET is so comparable to psilocybe mushrooms, it sounds exceptionally appetizing.