Check out the 10-ring forum here. Also, good job on chucking that buffer, Ive heard nothing but bad about them. And underwood ammo is the way to go, but when I looked yesterday they were out of all of their 10mm ammo. DT is way below advertised specs these days, and more expensive than underwood. Personally I run several aftermarket parts in my gun and love how my gun shoots. LWD ss recoil rod, ISMI 22lb recoil spring (wish I had gotten a 24lb, even when I shoot weak tulammo brand .40sw through my G20sf it cycles just fine), LWD 10mm barrel, 6lb trigger spring, lwd overtravel stop, Ghost 3.5lb connector, extended slide stop lever, xs big dot night sights, and a reduced power trigger safety plunger spring
...but, that's just me. This gun isnt used for protection often, but even when I do use it for protection the only change I make is I switch back to the stock barrel...Everything else has been completely reliable for around four thousand rounds now.