That whole FPS thing is misunderstood...much like horsepower. It's useless if you can't control it. An efficient and well managed 340 fps is certainly nothing to snort at. That said, for the firearms classification of 366fps or higher in this country, I try and keep my rifles around 370 with .2's (I only play on outdoor fields). I can keep the gun internals nice and loose which means they last forever. Concentrating on the air management and BB delivery I still get 85 yards+ out of my G36 (r hopped, etc,etc) and it runs all day on a 9.6V NiMh. I fire .3's out of it so the wind and foliage doesn't bother it so much.
As for a CO2 pistol, yeah my 1911 is a little hotter but still under 400 with .2's. 50 yards? No sweat with .3's. If it isn't shooting that far, it's broken. hehehe