I recenty replaced the tyres on my 430.
When i was looking at all the labels info it was very confusing - there were £50 budget tyres with very good noise and grip ratings compared to top brands whch were between £100 and £150 with very similar if not worse ratings.
In the end I went and bought mid range Avon tyres and my choice turned out to be spot on.
The original dunlops gave alot of tyre roar even at local driving speeds, they were very unforgiving on uneven surfaces and dragged on full lock.
With the Avon all this is sorted - they are very quote (car has never been so quite in the last 4 years), very supple and forgiving on uneven surfaces and the dragging on full lock has gone - very happy indeed.