Focusing with the E-P3 is pretty fast, even with the older lenses. I find that focusing with the 12 f2 or the 45 f1.8 is really fast, nearly instantaneous. That makes it fun to use. Even with the 14-150 focusing is ok, but it's not made for sports photography. Actually the whole system isn't designed for that. If you want to do sports photography you really are better off with a DSLR.