cdi, freaky that it's exactly how I felt on the grip, like a XT, which is pretty good on a p/s. I only have the Olympus for couple days, most of my tests were making sure it would work with speedlites. But the image performance is pretty good at iso 50 and 100. It weights 8.6 oz, so I am tempted to hold the 580 as support when shoot with the combo 
Mega, when you see it takes 2 sec to auto focus in low light, you might want to smash it against the wall like me. However, in manual focus mode, it gives focus distance in ft, which is quite accurate, considering p/s always has huge DOF.