I've got a Cannondale Supersix Evo Hi Mod with DuraAce 9070 Di2 11-speed. Recently have been practising standing start sprints up inclines and have been finding I have to pause for a moment after a few seconds to change gears after I get up to a decent speed. Got me thinking that sprint shifters in the drops might be a worthwhile investment.
Searching around for Di2 sprint didn't give me a whole lot of info on the web or YouTube, though I found several threads here, but they generally seem focused on modifications or non-standard setups. Did see some comments saying they didn't really use them during sprints, so before I go on, are they worth getting, are they useful in uphill sprints?
To get a standard setup, do you just buy the SW-R610 Dura-Ace Sprint Shifter buttons, take off the bar tape, plug the cable into the shifter and wrap the cable around the bars to take up slack, cut a hole in the tape, and then reapply the tape? They don't seem to be in stock in many places that ship to Ireland where I'm based, though I found them in stock in Germany here: http://www.bike24.com/p248407.html
Anything I'm missing? In terms of positioning, is it just a case of practising to see where I tend to position my hands during a sprint and then find a spot that's within reach of my thumb in that position, but not directly in the way so it gets hit by accident?