It depends on the ballhead in question and the 4x5 in question. I have a Manfrotto ballhead that's fantastic for my P645 with the 120mm macro (fairly heavy and lopsided) and it's fine so far with my Chamonix F1. But it cannot handle my Cambo monorail at all (so I have a Berlebach with a pan/tilt). As far as whether I like the ballhead with the 4x5, that's still up for debate. I don't usually need to move around fast with it, so another head might be fine. But I'm fine with it so far.