Just look at the price difference... it's not just about looks.
The 800 series sound massively better than the 700's. I auditioned the 816V and the 716V next to the MA RS6 I own now, and the 700's fell way short. The 816V on the other hand is really impressive, had to audition them 2 more times before I decided not to buy them
. They are as good as the RS6, maybe even a tad better depending on what your taste is, but they are bigger and more expensive. (in comes the missus)
When you put the 700 and 800 next to each other you will know: the 800's rule in every aspect and are well worth the higher price.