Something I have discovered in the last few days is that the wear rating of tyres does not correlate with the make of the tyre, but with whether or not it is considered to be a "sports" tyre. Low profile tyres such as 225/40 appear to be regarded as "sports" tyres and they usually have poor wear ratings no matter what make they are. I wish I had realised this before I bought my current Mercedes which has 225/40 tyres. If I had known, I would have bought something else!
There is a web page which gives these wear ratings:
I've been using Kumhos for the last 10 years. The first ones weren't fantastic but the latest generation (KU31) are excellent. The only problem is they are not cheap any more. I'm now trying Nexens. I ran the Winguard Sports through the winter (just as good as the Goodyear Ultragrips on the wife's SLK). I'm now trying the N6000 summer tyre. Seems really good so far and comparable with the Kumho but cheaper.
As above ^^ I've been using Khumos for the last few years, they are superb, but the rest of the world has woken up to them and the prices are rising.
I will be trying Nexens as replacements, as several colleagues have been singing their praises.