This is just a too generic statement. I have been using CC6 then XM2+ and now CC7. No doubt the XM2+ is slightly better in wet, but I didn't face any major issue driving at >80km/h during heavy rain with CC6 or CC7. The only thing need to avoid is hard braking in wet which I don't think XM2+ can help either. The comfort and quietness are both superior on the CC7 than XM2+.

Hey dude. How long u have been using ur CC7?
Does it have problem like goodyear assurance triple max 2? It is very quite initially then the noise become worst after fee years.
Btw, what is the life span and milleage CC7 can last?

I was on CC6 for 3 years before replaced it with XM2+ and on that for 3 years++ also, my experience is CC6 still quieter after few years.
Already on the new CC7 for 3 months++ now, super happy with it and if given 2nd choice, I will take it again without hesitation.
It is superior to CC6 in my opinion, super comfortable and quiet passing through whatever rough and uneven roads, make the car feel more luxury.
Been driving at >80km/h in heavy rain, didn't face any problem so far with loss of grip. Driving at 110-120km/h on highway and the only noise is from the engine and wind, tyre noise is almost non existent.