Good tires as well: my 2003 C5 game with Firestone tires and they were highly rated. Lots of good tires for touring purposes.I'm riding on Mickey Thompson Sport Comps. Leans more towards performance, but the ride is quiet, they wear well, and excellent stick for when more "spirited" driving is called for. Not run flats, so I carry a goop kit and compressor.
Another tire that I've heard great reviews on is the Firestone Fire Hawk Indy 500. Spoke to a C4 owner last year who was riding on them at a meet and greet, and he loves them. Price / performance ratio seems very good.