The barrel type.
Facts matter...Feelings Can Lie
I would be reluctant to buy a 320 without coonfingering it in person. Some of them have a trigger with roll, that feels very usable as is. The others have a definite wall, that while OK slow fire, is a no-go for me without a trip to Gray Guns or equivalent.
Likes pretty much everything in every caliber.
I would not spend 75% of the cost of a pistol on trigger work and shipping.
I think most would agree the benchmark for a pistol trigger is a masterfully done 1911 trigger from a guy like Bill Wilson or equivalent, and the essense
of such a 1911 trigger is the crisp well defined wall and icicle like break, same as a geissele or any other match grade rifle trigger.
The thing that makes the P320 trigger special in my view, is that it's the only striker with a crisp well defined wall instead of a mushy crush type of break.
My glocks all have ghost evo connectors and gen 3 bars which gives that rolling surprise break, I hate it, but was something I had grown used to over 23
years of glock use, my point is that it's amazing to me how someone could prefer a rolling surprise break over the crisp wall of the P320. To each his own I guess.....