One of the burdens of shop ownership is that of R&D - sometimes you must be the guinea pig for the sake of the business. This is a very new role for me since historically, by the time I adopted new technology it was not new anymore. Seriously, I did not have the new fangled index shifting on a road bike until some 21 years after it had been introduced. That's how far behind the curve I have traditionally been.
Two Wheel Transit applied with Shimano to be a Di2 Electronic Shifting Demo Center. This meant we needed to have a suitably equipped bike for the purpose so I volunteered my 6 Series Trek Madone. The system has been installed on the bike for almost 4 months and has proven itself to be reliable, accurate, quick and solid. As a matter of fact the battery just indicated that it was down to 50% which is proving to be better charge life than advertised by Shimano. The other cool thing is that there is nothing that goes out of adjustment with normal use - no more shifting adjustments or tuneups. My only complaint has to do with my clumsiness when stopping occasionally I initiate an unintentional shift that makes starting again a little more difficult until the shift completes.
I am going out on a limb and predicting that electronic shifting will be on the majority of road bikes sold 3 years from now. The introduction of Ultegra level electronic shifting is a precursor of things to come. Next will be mountain bikes and the XTR system. Time will tell if I am right.