I have tried various brands and thicknesses but always come back to Dunlop 1.0MM nylon, the black ones. It might be superstitious but I feel better playing with one. I keep one in my pocket at all times, even when heading out to work, I check for it like I do my wallet and watch like it is part of my everyday kit.
I do though for acoustic use the grey one, think it is .77 or so. I find the heavy picks too much for acoustic, which is odd maybe because the strings are bigger?
what do you all use and do you experiment?