If you use a one piece picatinny style rail, medium height rings should be fine for anything but a monster scope. For a 3-12x42 Nikon low rings were OK.

I personally like Warne Maxima steel rings and if available I get a steel 1 piece 20MOA picatinny rail. I have several Warne rails and 1 Nightforce. I am not an EGW fan, for me they are a product of last resort.