The OM-D has kept me from using the 5D until this weekend in which I grabbed the large camera again. With all those new fast lenses coming out, images will be even better. For now, it's a very viable alternative, and when you think of it, Olympus did get things right with this camera. I couldn't install the firmware (no software for Mac!) although some people have been able to. They say the wake-up time is faster, which is one of my very few gripes.