it has a full automatic mode, but if your going to be using auto all the time perhaps the M3 is not the car for you.
The DCT is all about being faster shifting than a human. It has launch control, optimum shift indicators on the tach, and a 8300rpm redline
. All of these are features you are paying for in a 60k+ car that you would never use in full auto.
there are other cars with full automatic gear changers that don't cost $2700 extra. The C63 is one, there is Charger SRT8, Mustang GT500, Corvette, etc...
You don't have a clutch, it still helps to know how to rev match which is a skill you pick up when you drive manual. The other cars listed take care of those responsibilities for you, and are still plenty of fun.
it says you drive an M3 already however, so either you drive stick, or you have used SMG. If you have used the SMG gear selector lever, then the DCT should feel familiar. It's just a whole lot better.
Anyway, good luck!