It depends on how you hunt. For sitting in a blind, get the M-7 because it's short. For fast offhand shots, get the 700. The few M-7s that I've owned were light in the muzzle and the sights tended to float when things needed to happen quickly.
The 18" rifles are particularly bad, especially in wooden stocks. A 20" rifle in a factory synthetic stock might be a bit better. Oddly enough, iron sights help because they put weight forward of the action.
Okie John