Noticed a few differences in the Gen4 23's... Here are a few photos and the things that I've noticed. It's still new and hasn't been fired, but I did do a polish job on all the internals. The trigger isn't as light as I want it but it will do. I also installed a ghost 3.5 connector and ZEX stronger trigger spring. Pics: Striker end looks a little different than the gen3 19 that I own. New G23 Ejector. 28926 printed on it. The extractor has a number 2 on it. No scratches on either side of the extractor. Which tells me it has free play in it.