You think the beretta D spring is awesome....wait till you try out a lighter 1911 mainspring . Ok so for kicks and giggles I got my D spring today and installed it in my Elite IA, and it was as everyone says, lighter and smoother. Then I remember a few people saying that they used 1911 springs. So I took out my RIA 1911 mainspring, it was about 8 coils short of the D spring. I didn't expect much....until I tried it. WoW was my expression w/ some laughter!! Since I reload my own ammo, I got one brass with NOTHING in it but one Federal pistol primer to see if I'll get a light strike. Low and behold it worked!!!! Now, I'm guessing if you reload your own ammo using a 1911 spring would be to your advantage since you can find out which primers to use. If you just use factory ammo probably stick with the D spring.