Yeah, doesn't the rifleman have 1/2 moa click adjustments? Versus the 1/4 moa adjustments of the vx1/2 series? That would make it slightly harder to dial in at the range, but I have one on a .300winmag and it has stayed rock steady for 300 rounds. I think it only took me 14 or so shots to get the reticle on the bullseye at the range, and I've never had to think about the rifleman since.
The VX2 is the superior quality of the two, but it also has a lifetime guarantee, allowing it to be repaired or replaced by Leupold if there is ever a problem. The Rifleman does not.