I've done them all and Lsd is the longest lasting by far and when you take to much and get to a place where you are not comfortable, lsd is the one that is gonna keep you there the longest. "Bad trips" are simply from processing huge amounts of information and being overwhelmed, and lsd will definitely take you just as far out as anything else.
Haven't had a bad trip on any of those. The worst for me would be shrooms. There were bad times but it turned out to be a beautiful experience. I've had a couple bad trips on DXM if that counts, even though it's not on the list