I have been doing one arm presses once a week for the past year. I saw them on World's strongest man and thought they looked like a sick lift. Tried it and really kind of like them. Single snatches too. I think it's because timing and balance are huge strong points for me. Just static butt strength, not so much, but add movement in and I seem to do better anyway. Plus, I believe it has helped my static OH presses, too.
Are you much better with one arm than the other? I am. My right is way better than my left, so I do left first, then only do that many reps with my right.