Right now I'm pretty much doing all of my free weight exercises with dumbells - presses, rows, and curls.
Originally the advantages seemed obvious - a better stretch, wrists not fixed, more stabilizer involvement, more symmetry, no lopping off of heads...
But you run into some problems when you realize that there are no five pound increases (at least not at my gym). I suppose I need some adjustable dumbells? Nobody has those. Ever. I mean, I could sweat it out and grab the next set for a ten pound increase, but that's not exactly sustainable progression. But it's either that every two weeks or so or get back under the bar.