I had a 4 inch 66 that was Magna Ported. It did really help on the recoil with full house 357 mag rounds. Shot those and felt recoil was more like 38 spl. target loads. But.... my gun had the red ramp front sight. Soot would blacken the red ramp and the muzzle blast coming up from the ports kinda melted the edges of the red insert. Never enough to cause it to come loose though. And as mentioned before, if shot in the dark, the flash will blind you temporarily.