Originally Posted by
GhostRider62
DA is obviously much lighter
DA 9100 = 2007g
Ultegra R8000 = 2303g
It's been a while since I've looked at a weight weenie dollars per gram chart. Is $1000 to shave an additional 300 grams good or bad? I guess it's probably not too crazy when you think about wheel upgrades, or think about the cost difference between regular and S-Works frames, etc. If the OP's final build is 16.5lbs instead of 17lbs, does that matter to anyone other than the scale? It's still going to be a really light, fast and awesome ride either way.
I'd argue that the intangible "cool factor" and bling of Dura Ace is going to be worth more than 300 grams difference, but I suppose that depends on the OP's ultimate goal.
Mostly if I were the OP I wouldn't worry about justify the cost.