I run one with the SCR-MOA reticle on a lowly Tikka CTR in 308. I agree with the other posts, it starts to get milky above 20x unless the day is bright. I had it out yesterday evening deer hunting and I had to back off zoom at 450 yards under tough light conditions.
That being said, I really like this scope and would buy again in a sec. I have run this scope hard at distance in competition (GAP Grind) and it more than held its own (finished top 1/3rd and scope wasn't the limiting factor 😜) against way more expensive setups. Mine tracks great, zero stop is solid as hell, and I really like the SCR reticle. I wouldn't feel cheated with the 4-20x, but I got the 5-25x.
Like others said, its no Nightforce, S&B, Kahles, Vortex Razor, etc. but its also half the price and 90% the performance IMO. If you want to get serious in the PRS world I would look elsewhere.