SGT45 posted about their SC base plate the other day and I decided to try one for my 320cRX and I love it. It extends the mag just enough for my pinky to fully rest on the grip. It's a nice little upgrade that gives you a better grip and feel without adding too much length to the grip, .125" according to their site.
Here is some photos of a quick comparison of the stock and NXGen base plate
Two base plates together
Stock base plate
With the new base plate
Stock base plate, pinky hangs off just slightly
Pinky rests on the new base plate perfectly
Here is the link to their site.