I like the grip on the G5 (which is the reason I don't have a G3). It's has a very nice feel to it when holding in my right hand, which is the way I carry my cameras when on a walk. The camera is connected to my wrist of course with an Op-Tech wrist strap. I think they are the best on the market.
The Panasonic cameras, for me, are much more comfortable to carry than the Olympus cameras as they lack a grip that I can wrap my fingers around.