Originally Posted by
TimothyH
Agree. Once you try Di2 you'll never go back. The only people who don't recommend Di2 are those who have not tried it. -Tim-
Timothy, I have tried it and loved it but out of the two choices the OP presented I would pick the Dura Ace. I would rather have the top end of a group rather than middle tier. If I had Ultegra, I would always want Dura Ace. Now if it was a choice between the two Dura Ace groups, mechanical or Di2, I would chose the Di2 but those weren't the choices offered.