Not a lot of difference, the only advantage, is in "felt or percieved" recoil and this is very contraversial. I had one that was not a Diamond grade, I over bored it and had chokes installed. I would not do that again, instead of making your patterns bigger it is better to learn to shoot small and hit big. The choke winchester puts in that gun (fixed full .040 constriction) is a great recipe for gaining yardage. My 101 unsingle Diamond grade with that choke, got me to the 27 yard line, but I could not keep a release trigger in it. Works great pull trigger, and I still have that gun but I will sell it. I have since moved to a Perazzi MX 10 combo. All fixed chokes and work done by Tom W. Precision Gold double release. Scott