I've done one as a fellow top, and it was fun. But I naturally prefer 1 on 1, so it's never been a huge thing on my mind.
I've done two as a bottom. Both times it was a hookup that wound up turning into a (safe) gangbang. Two of the hottest experiences of my life servicing guy after guy, but not something I want to do everyday. From what I've heard, it requires a lot of coordination to set one up (ours didn't, we had a group of guys horny and ready to go and just did it). Also, I've heard you can get some strange types who respond to the solicitation (I'm not a shallow queen, but I won't be taking just any guy with a pecker). So do it, safely. I'd say soft drugs are okay. I never do hard drugs, but soft drugs can relax you (not necessarily physically, I mean emotionally). I sometimes enjoy sex after a little alcohol, and I always use poppers. I'm sure if you care for 420 that could be fun. Just don't turn into Whitney Houston and Bobby and be smoking crack and tina, that could spiral downward real quickly. The drugs should compliment the main course of the sex, not the other way around.