I use a custom made Showcase yoke style capo. Bill Stokes, a well known banjo player, makes them.They're also know as a Elliot capo. I think Heritage G7 capo is also a yoke. They're pricey but well worth it. Very thin so can hardly tell it's on. I've got a drawer full of capos and theses are the best. Will never have to buy another.
Nice thing about a yoke style capo is they clamp down from the middle so very little if any retuning is necessary.