No clutch on a dsg. The clutch pack is an internal part of the DSG gearbox so don't worry about that.
Dual mass flywheel is one piece that needs to be swapped out about £600 parts and about £1,000 for the job all-in-ish.
They seem to be lasting from about 30,000 miles to about 60,000 miles roughly looking over what people have said here on the forum.
I had a new one replaced about 30,000 miles and it was knackered within 20,000 miles I've got it swapped out again and it's two year warranty by VW.
It seems the dual mass flywheels are not as good as they are as they used to be my old t5.1 van it lasted till 85,000 miles.