They're pretty good, the inside edges aren't quite as smooth in all cases an can occasionally dig into your wrist, but in terms of visual accuracy and quality they're generally almost as good as the real deal. My brother has a gen with a deployment, and the pin fell out and he was holding it together with a paperclip. I haven't had such an issue with any of my rep deployments, though in one the screw couldn't be removed so it was stuck on the strap.
Near as I can tell, the manual wind PAMs usually come with a buckle while automatic luminors have deployments. I prefer the deployment to the buckle, looks a little bit more like a "luxury watch" to me.