XM2 now already similar to budget tire range which the rubber compound will harden over the years to prolong the lifespan, nothing to shout about as even my previous Giti tires really last a long long time until serious crack only throw away.. 

What? CR1 is entry level tyre which similar to Hankook Eco2. It is definitely not comparable to Prime 3 who is much better in grip for dry and wet compare to CR1. CR1 is great in comfort and quiet but for grip it definitely out.

I dont know how can you comment CR1 is better than Primacy 4 and PS4 because I have CR1 in my new Alza which I felt it is moderate tyre. The tyre is quiet and good ride comfort, but the dry and wet grip is really so so and nothing much to praise AT ALL. Among entry level it is quite good but definitely not in the level to compare to Primacy 4 and PS4. I find this CR1 dry and wet grip is a bit weaker than Hankook Eco2.

Primacy is not quiet? Holy... are you kidding me?

You should avoid continental then because they are freaking noisy. Michelin PS NVH are usually okay'ish until you ran them down. The primacy should be a lot better not only with noise but also comfort with it's rounder sidewall versus PS flat sidewall.

I think the main aspect of tyre comfort is still the sidewall height. E class, I'm guessing 45 profile?? You cant get any comfort with 45 height tyre since you need to pump them quite high between 38-42. Those older round lights E class have slightly higher sidewall and very comfortable but ever since they changed to these sporty looks, well, the tyre has to slim down to accomodate the looks.