My ski / mountaineering tripod is a Manfrotto 190CX Pro3 with an Acratech GP ball head, less than 4 lbs. and works fantastic for my Chamonix 45N2 and everything else I put on it when I have no choice but to go light. Otherwise I use a 7+ pound combo of a larger set of Manfrotto metal legs with an Arca Swiss B1 head I bought in the early 90's.

I rarely have any issues in using ball heads for 4x5.