Well, you guys have convinced me to give them a whirl. I received a pair of CTT1 (and a matching S5, thanks, Dan Martin) the other day.
From the perspective of build quality, after reading some of the other posts I was anticipating more of a 'hand-made' look and feel. My first impression is that the product is well-made and executed.
The carbon footbed is very even and has none of the extra flashing that I expected to see. The finish is very smooth and clear, as well. The upper is well-finished. All of the stitching is even and there are no overruns. The straps are correctly cut and are flat-finished perfectly. The shoe includes several different types of materials (microfibre, mesh, rubber, etc.) all of the peices fit together very well. The joints are nice and flat with no 'hot spots' transferred to the inside of the shoe. The interface between the carbon footbed and the upper is flawless all the way around the shoe. I had heard that some people had problems with glue on the upper. There was none of that. From the perspective of fit, that may be another story.
I have been on Sidi for many, many years (in fact, since the rise of the manufactured shoe vs hand-made leather-soled shoes, I think I have only worn three brands of shoe). The fit feels very strange versus Sidi (think: Edward Green vs Allen Edmonds). It is all down to the 'bathtub' design of the footbed, but the design principle extends throughout the shoe and the design of the upper is also very close-fitting. It is quite a different 'feel', kind of like the difference between a slip-lasted shoe and a board-lasted shoe (come to think of it, that is a pretty apt description of the difference in construction).
I have a narrow ('D' width) foot and the Bont appears to fit me well. If you had a wide heel or needed a roomier toe box, I am not sure that they would work for you. The toe box, in particular, is much lower than Sidi.
I am going to try to 'heat mould' them this weekend and will report back.