I guess, one time you won't fuck yourself up. I remember, when I was a teenager, every time we dropped acid, someone would bring up "if you do acid 10 times, then you're considered legally insane". I don't know if it's true, but if it is, now I have a criminal defense. Tabs are the best to do. I only had one bad trip, but as long as you're with friends (real ones), you'll be alright, in fact, I was good enough to drive eight-hours later (though the lights on my Mother's steering-wheel were more exciting).