VarX II have less horz and vert adjustment, plus for the time period typically had less coating on the lens. For many years the VarX III were the top of the line sporting scopes (now this is the LPS). For the money I would pick up a low usage VarX III in 2.5 to 8 or or lower power, however, most end up with something more like the 3.5 to 10 (or even higher power).
If you can fit it on (short tube) the 1 3/4 by 6 VarX III makes an iteresting choice for a scope, either Deer hunting or tatical. Plus if you can get is zeroed the VarX II in 2 to 7 is a nice general purpose scope (have on several 22 LRs).
The M3 can do all the adjustment in one turn of the dia for range, liked by one friend who does rife shooting for a living (which one friend does and currently has sand in his boots).