I guess, better to have one and not need it than need it and not have one. I have both 0 and 20 MOA and have never shot far enough to need the 20 MOA. But, it is there if I do and I have never had issues zeroing. So, if you think you might need it, I don't see any reason not to get it. About the only reason not to is most 20 MOA rails cost more than the 0 MOA rails.