Issues can depend on the caliber. The 9mm Gen 4s had some recoil spring assembly issues in the beginning that have since been fixed. That said I have seen my share of erratic ejection in new 9mm Gen 3s and Gen 4s. I do really like the Gen 4 texture.
If you don't mind me saying I notice on your posts you've gone from handgun, to revolver, to shotgun, to Steyrs, to Glocks all in a really short time. I can't tell if you're building collection or trying to figure out what you want for a first gun. My best advice is to get to a range that rents and see what you like best. It's definitely worth the money.