Both. Just remember that some of the time, you are going to be loosening a bolt that has really been tightened. A ball end just won't do it. The bigger the size, the less this problem becomes.

In addition, some long arms are also necessary. "T" handles are also nice. I've got a set of long reach metric and imperal. T handle Metric and Imperial. A huge selection of regular size imperials. Quite a few 1/4" socket drive ones. Not a single ball in the bunch, I need to go over to Enco and pick up some. I still never have the right one.

Don