The Cle de Cartier (Cle - French for key) is one of the nicest, cleanest designs I've seen from Cartier since the Santos Dumont. I believe the jury is still out of the use of the "key" rather than the "Crown" but given their whole line is named after said key, I'm sure their R&D department has thoroughly tested the idea to make sure it works in everyday situations. But then again, not everyone wears a different watch everyday and given that it's an automatic, I suppose you set it once and off you go. no need to touch the key again till the shorter months where you'll need it to advance the date. Plus, I'm sure the target market for this watch will have some sort of watch winder at home. whether that be an actual mechanical devise or someone you pay to wind the watch for ya.
I like these oval shaped cases. A nice through back to the sixties and seventies where these sort of cases were all the rage. Omega (Constellation, Seamaster) and IWC (Yacht Club) comes to mind immediately. It's a shape that's worked extremely well in the past I don't see why it won't work again today. It's distinctively Cartier, thanks to the Roman numeral hour markers and the blue sapphire used on the crown, sorry, key. Perfectly balanced and retains the classic Cartier elegance and design elements that we are so accustomed to.