I prefer to have items turned off. Not because they're random or cam get in the way or anything of the sort.
I prefer to have them off because I never get to enjoy them unless I play the game by myself.
I have a nasty habit of just chucking items at people, instead of actually using them. I just throw them around at people.
I've actually gotten quite good at aiming the item so that I can nail someone while they're in the most inconvenient of situations. Like, say, when they've flown off the side of the level and are close to the death zone.
The problem is, I don't get to chuck items around with my friends. Because they deliberately go out of their way to keep any and all items out of my hands. Me, specifically, because they see me as a nuisance when I get a hold on one.
It just isn't fun when I don't get to do anything with what we're given. If you're not going to let me use items, why have them on at all? They may think my throwing items is obnoxious, but they're even more obnoxious to keep half the fun away from me and it just really ruins it for me.
So I always turn them off and keep them off because everyone I play with is a total dickwad about not letting me near them.