Of the bikes I have weighed with the same 105 componentry (and size) the Caad10 has been lighter than such carbon bikes as the Specialized Tarmac, Felt, Giant etc. In fact the only bike that had dipped lighter on the scale was the SuperSix, and the Hi-Mod version is lighter still, and that would make sense as they the fork and components are the same but when you make a carbon frame you do not need to leave extra material on the end of the tubes for welding and you can place the carbon where it is needed and take away from where it is not so the carbon frame of the same design should be lighter, also a carbon frame by the nature of the material itself woulf be more comfortable on long rides, so taling an already comfortable aluminum frame and using the same design to build it in carbon should increase comfort - judging by all reviews this is the case. although I would suspect that a Specialized Tarmac with their top end Carbon lay-up would be lighter than the Caad10, but that frameset alone would set you back over twice what a whole Caad10 with 105 would cost. The Caad12 is even further refined and lighter still - I especially like the fork as it gives a look similar to the old-school colongo straight blade forks. I also like the spec on the 105 including Mavic Aksium wheels over the RS11 wheels that came on the Caad10.