Most of the time, I use 6mil blue nitrile. I keep a pair of mechanics gloves on hand for when I'm heavier stuff, and leather work gloves for when I'm dealing with hot stuff.
The only time I go gloveless is when I'm doing something where I need a lot of fine dexterity. Fiddling with SU carb linkages can be one of those situations.
In general, though, I use gloves for everything. I even keep a box in the trunk of every car if I need to do a roadside repair.
I'm a chemist in my day job and always have gloves in my lab coat pocket and some of the other stuff I wear around work. There's also a box convenient to all of my work places. I put on gloves pretty much any time I'm dealing with chemicals, whether at work or at home. Funny enough, the only time I don't is when I'm messing around in the dark room, and that's mostly because I can't stand the loss in dexterity(I can't load film on developing reels with gloves on, for example, and also have issues handling printing paper).
The only issue with disposables is that I've had them poke through and not noticed it.