Ignore the bulk of this flyer from Sig. The dimensional differences are interesting, as Sig's are considered to only fit those with large hands. Mine came with E2 grips, but I purchased a short trigger and the all important single action slide catch.
Setup as I'm currently running it.
Top is the SAO slide catch. Keeps the thumb from riding it, preventing lock back after the last shot.
Only downside is that it doesn't work with grips other than the E2 because of the cut-out.
The OEM grips above are nice for several reasons. Fit my hand better, though they are larger, extend below the frame to make a slightly bigger magwell, and I think look better. E2 grips have a more aggressive texture, slimmer, don't have the "hump" which interferes with a thumbs-forward grip....and the don't have a slide catch cutout and are therefore able to take the SAO slide catch. That is the defining point for me. It should be a standard item on all Sig P226's!
I'm using a 9mm recoil spring instead of the standard .40/.357. Both work with my light reloads, but the recoil impulse is better. Sig is smart to paint their springs for easy ID!