Most I ever did was two light tabs. I was at a friend's house, and he was gonna drop with me, but we smoked quite a bit of weed and he said he'd lie down for a second and take his in ten minutes. Ten minutes later he was out so solid I couldn't wake him even when I shook him. I still had a pretty great trip, even though I was alone in his house and couldn't wake him up. Except for when I went to the bathroom, and about 50 hands slapped the second-story window from the outside, and I freaked out and turned and saw in the mirror that I had no eyes.

Blegh.

edit: Yeah there's a huge draught since those guys got nailed, and as for the comparison, acid is much more edgy and intense than shrooms. Shrooms are drippy and philosophical, but still giggly.