Try reading this: http://www.amazon.com/dp/B008DZEWF8 for another point of view on LSD and the impact it has.
My personal belief is that, moreso than any religious belief, it's important to manage the karma we experience-- to learn from the bad, and not to turn the good into bad by becoming hubristic. Negative karma will ripen, and the important thing to do is to let it do so in a way that doesn't turn into recursive negativity that generates more bad karma (either for oneself, or in negative actions toward others). What bothers me about these drugs is that they seem to take away some of that ability to manage the karma that comes through. You experience a lot of sudden karmic ripening, which is interesting, but the insight that needs to develop over time isn't there for a lot of people, and those I've met who I think could use those drugs effectively (rather than haphazardly) often have no interest. I've been very unimpressed by most of the drug mystics I've met, because most tend to be sophomoric and unbalanced. I'd rather talk to a zen master any day of the week.
Personally, I'm not interested in using these drugs at this point in my life, but I don't think they should be illegal or as stigmatized (in the larger society) as they are. They're probably less dangerous than alcohol. The problem is that, if you choose to use these drugs, you're trying out a technology that's still in the very early experimental stages, mostly because the research has been (wrongly, I would argue) outlawed.