Because, like me and the majorioty of other people on here, you never drive your car anywhere near the limits that makes tyre choice in this range an issue. Sure, I'm not saying put ditch finders on, because that is silly, but a vred sessanta is not going to perform any better or worse than a CSC3 given the style and type of driving we both do. It's not like we go every weekend to the track. A CSC3 is not going to keep you on the road any better than a Sessanta. And, unlike a tyre review where I've lived with them for the best part of 4 years, I can wholeheartedly say they were always better than the GSD3 and the Asyms I had on there last year, without doubt. Quieter, gripier, longer lasting and they stop just as well as any other tyre I've ever used where I've had to stop quickly.
I'm in the same boat as you though. I've never tried a CSC3, but I can't say it's going to make my driving world a better place to be. However, you should at least try the vreds for a full round, and then you can be free to impartially comment on them to your hears content