Unless you create a transmission that reads my mind, or can see the road and surrounding traffic it will not shift "better". Faster? yes. More smoothly? yes. Better? No.
They're an option on the more expensive Audis and a few other manufacturers have them.
A quick search for "CVT reliability" produces pages of horror stories related to the Audi (and other) CVTs.
The CVT is only available on the A4 and A6 (not the A3, A5, A7, A8, Q5, Q7, et al). Also, the CVT is only available with the smaller engine options. Finally, the CVT cars are front wheel drive only, no quattro available.
That is what I mean by "not mature".