I second Kelly621's advice. GWX and NYGM, using MultiSH3 so you can bounce from one to the other. I have a LSH install also. Looks interesting, but I have to make a SH3speech module for it and haven't decided what layout to make it for.

Right now, it's NYGM with Hitman's optics for me. Bare bones, no fancy graticles, just a couple of hand-held wiz-wheels. Very U-boat feel!