I little behind in the thread but I'd like to do an update to what I've found. I did low light non scientific tests on a few scopes and this is what my eyes have been able to tell. Here are the scopes. VX3 4.5-14x50, VX3i 4.5-14x50, VX5HD 3-15x56 firedot, NF SHV 5-20x56, Swarovski z6i 2.5-15x56...