I shoot a Burris ff3 on my Ruger Redhawk 44 mag with a 4.25" bbl. groups vary with ammo PCSWC 240's running 1000fps are tack drivers. speer Deep curl 240's at 1250fps open up just a bit but there hasnt been an animal yet that has noticed 1/2" difference. That said 1.5-3" at 50 yards off of shooting sticks is common. consistent 1.5" off of the bench and bags. at 100 I am in the 3-6" depending on the day I am having and if I have to turn the dot all the way up and deal with dot bloom.
My wife's 6" Ruger gp-100 357 with a Burris FF3 mirrors this accuracy at the same ranges. 158 grn SWC at 1000fps for practice and 158 grn xtp at 1350fps.
Aging eyes pushed me to the red dot sights for hunting. being an accuracy snob pushed me to scopes. I use both, for different reasons. However if I have a handgun that I plan on pushing past 100 yards I will stick to the scope for the precision aiming point every time.
good luck on your decision.