What kind of personal experiences? I can give you good ones and bad ones, on both LSD, and Mushrooms. Never done DMT, but wouldn't say I wouldn't try it at least once if given the opportunity. I haven't done any psychedelics in years though, and probably wouldn't ever again unless it was DMT, just to have the experience. Also done peyote too. I haven't done ayahuasca either, but Ive heard it's insane. I think alot of people should at least experience hallucinogens. As far as all the other drugs, that's another story. You have your opiates, your amphetamines, benzos, and then cocaine. I don't consider weed a drug, so I'm going to say best drug would be Opium, worst would be Heroin as far as my experiences go, and I know that may sound weird considering how closely related those 2 are but that's just my personal opinion.
I can't comment on everything in red's post but can say that I agree with the above 110%. Haven't tried any psychadelics in 15+ years but will say that at least twice tried the half a hit suggestion and it was great. Tried the larger dose once (Black Fly maybe?) and it was very much mind expanding but also very scary.
I've heard that X is the best. I've also heard that coke sucks unless you get it in, say, Costa Rica in which case it makes you feel like Superman. I've also heard that shrooms and acid are ok if taken moderately at a young age but then you kinda outgrow it. I've also heard that the 'molly' form of X is really awesome. Not sure if any of this is true though.
Never done any drugs really. smoked pot in amsterdam once. No good. Didn't get high but had that "stupid" feeling the next day at the Anne Frank House. I would possibly try the following: Weed, coke, and really that's about it. synthesized drugs cooked by hillbillies or some criminal enterprise scare me. Maybe mushrooms. Really my biggest fear is getting a bad batch of lsd or something and being brain dead. That pretty much keeps me from ever doing any of that stuff. Then stuff like heroin or opium just isn't going to get into my body. They say it's too good and you'll get addicted. I'll never find out.
X is wonderful, only problem is real MDMA is extremely hard to find. Tirk if you are really thinking of dabbling with mushrooms or LSD, i would be glad to give you advice to make it a great experience.