I might disagree with the 2 previous guys (although very scared/brave to go against DJ's advice

). At 6'2" & 110kegs, my first sup was a 11'6" Nalu and I still have it. I had no surfing background either - with exception of some windsurfing, albeit flatwater mainly.
The 11'6" is a great flatwater cruiser for touring on, fitness paddling and surfing in small beachies & breaks. I've had my each of my 3 kids on it with me, my dog, and the wife paddles it also. In saying that, I haven't ridden the 10'10", and although I doubt that it could glide as well, it could be good also.
Demo both & make the decision before buying.