After almost 20,000 miles of mixed use I have order another full set of RainExperts. These are not the tires for you if you are a boy racer and push things to the limit. But if your priorities are safety and comfort in typical British conditions then get these. Even when worn down to 2-3 mm they feel much better in the wet than the Michelin Primacy tires that were fitted from new. I can only compare these with the Primacy on my car but I would say:
Dry Grip - Primacy slightly better
Wet Grip - RainExpert much better
Feedback - I'm not a boy racer
Progressiveness - I'm not a boy racer
Wear - No difference
Comfort - RainExpert better
Noise - RainExpert quieter (I was surprised by this)
Snow/Slush - RainExpert better (but it's not a winter tire)
Fuel economy - Primacy perhaps slight more efficient
Buy again - Have done

The best tire to buy if you live in the south of England! Will only buy this tire for England.