In-Body IS vs. Optical IS

My own direct comparson was between a G2 and the OM-D, using the 100-300 at its long end.

A dozen shots each, with a shutter speed  of 1/60, the OM-D had more sharp shots.

Certainly not an exhaustive or conclusive test, but enough for me to prefer IBIS, all the more so because most of the lenses I use don't have OIS...