I also use an F2, but with a DP-2 prism; it meters in ridiculously low light--and I think the DP-12 prism is even better in this respect.

The F3 might be a better choice for you because it's smaller and lighter. You have to hold one in your hands to appreciate how small it really is--pictures of the camera make it look huge. One of my problems with the F3 is the notorious backlit display button that is really hard to push and doesn't work that well anyway.

Personally, I'd stay within the single-digit F series because their finders are larger and more accurate, and you have a nearly endless list of focusing screens to try.

Shooting with the 50 1.2 wide open is DIFFICULT. When I first got my lens, I thought I got a bad sample because all my shots were soft. After a few weeks of practice I realized just how narrow the depth of field is at f/1.2--even at long distances. The lens is surprisingly sharp at 1.2 but you have to nail the focus PERFECTLY.