I have this rear sight on my Optima V2 and I really like it. Much better than the factory rear sight, makes for a longer sight plane and yet is open enough with the twilight eyepiece, which it comes with, to see well in waning moments of legal shooting time.
I did have to go to a lower front sight with mine. I was maxed out on the rear sight to get it sighted in and I was still about 1" low at 100 yds. I ended up with a little lower front sight but also one with a finer fiber optic which made longer distance sight in easier.