I have a SIG P320 (full size) that even with the small grip module is still a bit larger than I like for my hand size.

Does the M&P full size (9mm/40) with the small grip insert have a smaller or larger grip and trigger reach than the P320?

I'm interested in this as a range/home defense gun. I recently bought a Shield 9mm as a daily carry.

I had a 320c 45, and now have a first gen M&P 45. I do believe the small module on the 320 felt smaller than the 45 M&P with the small blackstrap. However, I can hold the M&P higher than the 320, so I shoot it a lot better.

I have a P320C Medium and find my M&P 9 with the medium insert to be the closest. I find the M&P to be the better fit for me.

I shoot a M&P 2.0 .45 full size and use the small grip, but just holding it without the strap on it feels like I can get the right grip. bigger hands and short fingers I guess.

Goldstar225 Go down to a gun shop and ask a to handle a m&p compact or full size and ask the sale person to remove the grip to see what size it is . If not small ask to get the box for it and try the small grip insert !! If they will not help you they a second class gun shop .