Bikes, hills & centuries...question

[LivetoRide]

I too, would go for comfort, but it depends on which you like more and what your priorities are (comfort on longer rides, etc.). Remember that having a fitting done (and swapping stems, etc.) will allow you to somewhat adjust your position on either bike so if you perhaps feel more "right" on the Tarmac but are wanting a bike that will be both as effeciant and comfortable as possible on longer rides, that you can set your position up on the Roubaix to more match that of what you've got on the Tarmac.