I have ignito, strato and primorac carbon.
I play with primorac carbon now and putting the two others for sale. I also played with a friend's carbospeed a lot.
Starato is thicker than PC, and the top ply in particular is thicker. It has more vibration and higher throw angle and is more bouncy. I find that low throw is a defining property of most hinoki carbon blades but xiom blades are an exception.
Carbospeed is the other way around: thinner top ply and thicker core.it sends fast secure balls with low error rate but with little spin, which makes rallies long as the opponent can easily block them, unless you exert significant effort in your loops. Spin generated by primorac carbon, with the same technique makes rallies shorter as opponents get fast and spinny balls.
Ignito is thinner than all the other blades, with top layer of almost half thickness of the top layer of strato. It is less stiff significantly.
The 2 Xiom blades have a somewhat oval shape that is wider at the bottom.