Mizuno brought out a copper set of MP 20's a year or so ago and before commenting here I looked at some used ones on eBay, they just look rusty to me. The reason why I didn't buy chrome MP 20 was due to the part satin finish, not shiny enough.
It’s a yes from me, I do really like them. I also like the fact that the copper will tarnish over time so you’ll get a very personal finish. The only thing is I’d have to buy new wedges to match ?? If only I could hit them well enough to justify owning them!