I've just changed from factory 16" steel rims with 215/65/16 to Ronal R69 18" alloys with 255/45/18 Hankook S1 Evo3 tyres. So far I am pretty happy with the Hankooks, though I do sense more direct contact feedback when hitting sharp edges/holes on the roads.
However despite having chose the Hankooks for the low "A" low fuel and noise rating, it has kind of surprised me that my average km/l went from 14,8 km/l to 12,6 km/l with a semi loaded van. Noise wise they are very decent, and I would say even better than the midrange tyres I had before.
I am considering going down to 235/55/18 tyres for my winter tyre setup in October - to mitigate some of the fuel efficiency loss.