I have had these for about 8 months now. I have them in white, wish I could justify buying a pair in silver as well.
I weigh 165 (as a reference). I currently have plain sole inserts, not carbon. The boot is very comfortable in all conditions. It gets very hot here and these ventilate very well, in the winter I wear a booty. For my style of riding (mostly rolling hills and distances between 30-85 miles) the stiffness is very comfortable while still transferring most of my power to the crank. I have a narrow foot and they fit well without any rubbing or discomfort in my heel.
I believe that what you buy for your foot is the most important purchasing decision. With that said, I will be buying these again!