I really don't like Kahlers, but I wouldn't call them "crap". They're just so maintenance intensive, gotta keep them wheels moving, and feel kinda weird if you're moving from fulcrum units. The quality on the USA stuff is solid. Like, really solid machining and finishing. Materials are good too. They can keep tune decently as well, at least for a non-locking bridge. You just have to seat the ball end of the string really well and not dive far enough to dislodge them.