I sent my two 320 compacts in for the Voluntary Upgrade one day apart. The first was back on the eight day from when it was last at my house. Amazing turnaround. The second one took an "extra" ten days. I have no problem with that. It is really exceptional for this type of work.

The older of the two 320s came back with a new feature. Even a gentle insertion of the made makes the slide close from a locked open position. It never once did that in three years.

The newer one, bought two weeks before the Upgrade announcement, does not do that.

The triggers feel identical and at least as good as before the upgrade. The newer one feels better than it was. Note that trigger wasn't really broken in. I shot barely shot 150 rounds thru it.

Before shooting today, I added Talon grip tape to one and Springer Precision to the other. The Talon offers superior coverage and looks better.

Guess there is no concern about the new "feature" My MP 9 full size gen 1 does it too.

Just about any semiauto will do that with enough force. If it's way too easy, I'd look at the slide cut for the catch and the catch itself. If the cutout or catch that engages the slide is rounded, it will slip off easier.

The physics behind it is if you jar the frame, especially somewhat towards the muzzle, the slide doesn't move immediately with it, which release the friction against the slide catch lever, allowing it to fall back down out of the way and the slide goes forward. Some are easier than others, some people like it, some people consider it a safety concern. If you don't like it, call SIG.