"Anything that is built well, has good adjustment range, and holds a zero."
PSA is running a special on the Magpul MBUS PRO ($124.99 vs $180ish) . Well built, robust etc. I bought a set some time ago for my 308.
You could cheap out like I just did on my 300 BLK with these (I try not to disappoint, especially you, Ron <laughs> ).