I'm finally building the commuter I've talked about for two and a half years. It's going to be a Long Haul Trucker frame. My original plan was to upgrade my CAAD10 to Ultegra 6700 and slap the 105 on this one. The main compatibility issue I have with that is the Ultegra triple crank on the LHT (FSA compact double crank is BB30 and must stay with the CAAD) with the 105 double shifters and vice versa. I want STIs on my LHT, as I'll be navigating the streets of San Francisco and for personal preference.
Can I get away with a double on the LHT? Will a 52/39/30 give me that much more than a 52/34 when weighted down and likely going uphill? And could I even put the 105 shifters with an Ultegra compact double?