What parts though. Specifics?
I have installed the race hammer, adjustable sear, extended firing pin, ultra light firing pin spring, short reset trigger system, new pins and springs, the new disconnector and an 85C trigger on two of my guns. One gun has all of that plus the reach reduction kit. The other one has all of it except the 85C trigger. All of mine also have 11.5# mainsprings. These modifications make a world of difference. There are quite a few folks on this forum who do this as well and all reports are excellent. I am most certainly a satisfied customer.