Optimal without going over the top seems contradictory. In any case, to take full advantage of your MPR you should get as much magnification as you can. Some shooters will say that a 2-7 or 3-9 is all the scope they ever use; and no doubt they are right -- that's all they use. Low magnification scopes won't let you take fuller advantage of the MPR's accuracy.Wondering what might be optimal for a max 100yd shooter, without going over the top so to speak...?
I love a Sightron SIII 8-32x56 on my M54 for 100y shooting. Beautiful scope. I typically run it at 24x at 100yrds so that seems to just about right for me.