A new barber opened shop in the town right near me. And he is doing straight shaves!

But he is using a true junk shavette style razor, that I can tell he is not happy with, and I know that my face is not happy with it either!

I am working on getting him into real straights, but for the business, he has no choice but to go disposable. So I was thinking about getting him a good razor to work with. (the more shaves he does, the better he will get, the better MY shaves will be!)
So, my question is, Is there any actual difference other than price and scale material between the various types of Feather brand Club razors? I see the SS , the DS, the RG (am I missing any?)
If there IS, is it enough to warrant one over the other?
They do all use the same blades, right?

All info is appreciated!
Thanks guys