Another factor that may be an issue for some is the closer to the bore, the less parallax you will have shooting at varying distances.
I shoot matches where ranges can be anywhere from 10 to 50 yards.
When I was using high mounted Ultradot Matchdot, I would have to adjust down 4-5 clicks going from 10 to 25 yards.
Now with my slide milled RMR so close to the bore no adjustments needed. Shooting 357 Sig.