It mainly depends on the size of the front lens element (objective). High mag scopes tend to also have a large front lens. The old Leopold 20x-50x with a Premier Ret booster are actually 10x-25x but the front lens is 50mm (I think?) and they are re-parallaxed so the max distance is around 80m. Some snap in really well and the 2x booster just gives a larger image (and also reduces the light level - bit like a teleconverter on an SLR). So in theory having the Premier Ret booster removed should result in a 10-25 with just the same snap. Gaps are quite small though.
So, I think you might get something that works with a lower mag but not if the front element is small (e.g. 40mm or less), Working with one may strain your eye for FT ranges.
So - the reason why March and S&Bs are so expensive is because they are bright and have higher quality (large) lens elements. Nikkos, I have had, range well but the image is never really in sharp focus - more not quite so out of focus but that is all you need to range.
You do need to try as many as you can with club-mates to see what works for you.
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