Hmm, I've always found Falkens pretty good, but then that has been on lightweight performance cars, nothing like an A8 sized uber-cruiser.
http://www.camskill.co.uk/m61b0s315p...5_18_245_45R18
This is the page I am looking at for selections. I had thought of the Falken Azenis tyres. The Vredestein Ultrac Sessantas and the Continental Contisportcontact5's aren't much more. I'll go with one of those, I think. Never driven on a bad Continental in my time...