I've got some Ultegra 6800 wheels. Nice wheels, but i am no faster on them than the RS21 wheels they replaced (saved about 200-250g in weight). If i could go back in time, i'd go for some Fulcrum Racing Quatro's. Only 85g heavier than the Ultegra's, but with a 35mm rim depth and 17c internal rim width, i reckon these would be faster. Can get for £190 too.
I thought it was a great event. Bike course worked really well and compared to other courses i have done, pretty good surfaces on the whole. Few sections were a bit rough. Managed to extract the elevation gain and i have it at 1148 metres and my gps tends to under play it (had Outlaw course at 820m and they say about 935m).