some sales people (many) have no clue but like to act like they do.
I really would like to punch these type of sales people who just are too lazy to look into what they are supposed to know about. It's their job to brush-up on the cars they are selling. But bottom line it's a 7-speed.
I would suspect the DCT to be slightly quicker but don't expect the DCT to change the M3 to something quick like a GTR.