Have a 320X compact inbound.
Was looking at Sig's site and saw some modules. They have a 320x compact, with sizes.
Guessing the gun will come with a medium module?

Thought about buying a second small and stippling it some, saving the stock module.

Big difference between the small and medium modules?

It’s noticeable in the standard grip mods. Never seen a small X series grip module though so I can’t help there.

It should be a med. grip.

This is what was posted on the Sig site. XCompact Polymer Medium

You might want to play with it a little before considering any mods. Mine fit me perfectly as it came.

I think all versions of the P320 come with medium. Mine has the X Carry frame. I got a small X version from Osage. It’s not much smaller. My hands and fingers are actually larger but the small just fit me better between the web of my hand and knuckles. It may only be 1/4” difference but it did suit me (and my wife) better.

Just try the medium and see how it works out. It’s not a dramatic change.

For me, the smaller grip made quite a difference. The smaller grip is similar to a Glock grip/diameter,(minus the finger grooves) and was quite comfortable compared to the medium.