Style: yes. My boyfriend is super fashionable and metrosexual and I'd let him dress me 100% of the time, but he's always like "babe, just wear what you like, you're not supposed to dress for me." YES BUT I LOVE EVERYTHING CLOTHES YOU LIKE.
Size: I think it depends on the item. Jean size or dress size, nah. He could most likely chose my size in tops, sweaters, etc. Bra size...I think I've told him but IDK if he remembers. Shoe size he'd probably get.