I had kw V1s on my last mini and they are a very good set of coils as you say with kw you pay a bit more for the name and the inox coating but you could easily buy coatings and apply them yourself.
I loved the ride of v1s far more compliant than standard but the car had noticeably more grip when you threw it into bends, car also felt a lot more composed. The standard mini shocks and springs are crap imo they seem to find a perfect middle ground between being uncomfortable and allowing for lots of roll