I don't have a G2, but I'm shooting a contender (they are interchangable) and I can tell you about the 7x30 and the 22 match barrels. I've hunted with it for several years, and on deer sized game and smaller, the 7x30 is an excellent round out to 200 yards in the pistol configuration with spire point bullets. As far as contender calibers, it is probably one of the best rounds to shoot, IMO. Recoil is minimal, and it is my favorite by far with the 30-30 running a close 2nd.
The 22 match is another one of the barrels that I won't sell. Super accurate, and just fun to shoot. You can't go wrong with either of them.