OP, I think many folks will agree that there are so many really good choices....
It may be helpful to provide the following:
-budget
-barrel length
-intended for range only, going to see heavy, rough use, etc.?
-to what distance do you wish to use this firearm?
-CQB/in-home defense?
-fixed or variable magnification?
-or do you want to use a 1x optic with a flip out/over magnifier?
-at what height over the rail do you wish to have the optic? (alternatively, do you want absolute or 1/3 co-witness with your Magpul BUIS?)
One of my 300 blk pistols is a suppressed DD4 PDW (now an SBR)....
I have it set up to be for in-home defense. I have a "mini ACOG" TA45 (1.5x24) with red crosshair reticle. I cannot use red dots or green dots because of the severity of my astigmatism. This particular ACOG works really well as I can use BAC (again, my vision creates lots of challenges).
If you can answer some or all of the above, I think that it will help folks provide "better" recs to suit your use and purpose for that particular firearm.