Do you want to shoot fast or precision?
If you want to shoot fast the Geissele 3gun triggers are great, but they are designed for fast accurate shooting.
If you precision, I would go with a Larue MBT in hard to beat.
I have 3 MBTs and G2S and a S3G, the S3G is great for 3 gun, but in my hunting rifles I prefer the MBTs.