dura ace

Hi All Does anyone have any opinions on whether it is better to buy a new bike with Ultegra Di2 or Dura Ace mechanical please? I know it's personal preference etc but just wanting to get some feedback. I enjoy cycling, cycle twice a week outside (and another 2-3x indoors), do 70-100 mile...

Hey guys, I need your help to pull the trigger on a shiny new road bike (as early as this weekend)... About me: 30 yrs old, San Francisco, 6'2", 175-180lbs depending on last time I ate a burrito, have proven to myself over 3 years that I am "in" to cycling. I do 2-3 20 mile rides/week in Marin...