I use target reloads (about 750 fps), and I am the limiting factor, not the Pointman. Using a sandbag, 1.5" is normal, I get really smiley when I can get a 2.5" group two handed, and downright ecstatic with 2.5" one hand shots, usually more like 3.5"
the DW shoots better with iron sights than my safari (olympic arms) matchmaster with a tasco optima2000 slide mounted red-dot, but when the eyes start to go, the red-dot is better for me for timed and rapid fire.