I have narrowed my bike selection down to either the Cannondale Slice 105 ($1799) or the Cannondale Slice Ultra Di2 ($3300 after upgrading to brake lever shifters). I am fitting on both the 51cm and 54cm bike and would have to say I felt more powerful on the 51cm with neither bike being dialed in 100%.
My question is this:
- Do I buy the 105 mechanical, add in a left side only power meter ($500), triathlon skin suit ($300), and aero helmet ($200), upgraded tires ($100), upgrade wheels ($900).
- Do I buy the Ultegra Di2 model, add in power meter ($500).
With the Shimano 105 being 11 speed I am under the impression that I could covert over to Di2 down the line and not need to change everything out (am I mistake about this?). I want to buy what will make me faster and have been told that training with power will do so. But from a technical standpoint everything that I am reading is saying that an upgrade from mechanical to electronic doesn't really lead to "free speed".
I appreciate your advice in advance.