Last time around I went with Bridgestones, $2600 out the door with mounting and balancing (beads). I have found if properly maintained (cleaned with no petroleum based products, inflated to spec, frequent checks for road damage & covered when not in use), tires will last well beyond 5 years. I have always gone 10 years and other than some small sidewall cracking (only seen this on the Michelins), I've never had an issue. I usually check out the interior of the old tires when I replace them and so far, they always look like new (no visible internal cracking). Good luck.
Lou
05 Travel Supreme Envoy