Have not made the switch, but I do have both, although mine is a 997. Not a lot of help here, but I could very easily DD the 997 GT3. I understand the 996 version is not quite as comfortable, and makes it harder to be a DD.
You'd miss the comfort and convenience your M3 provides, but of course you'd be trading on more performance.
Was just driving the GT3 yesterday and it always impresses. When I'm in it, I just want to keep on driving.
Last edited by CPB; 03-06-2012 at 11:42 PM.