I carry two, but drooped my front wheels into a ditch at night in bad weather a few weeks back. I was able to jack the front up but the maxtracks were on good as a bridge. I now carry two lengths of timber 145mm x 50mm x 1200mm long as well as the maxtracks. Probably won't every do that again but I wish I would have had them with me at the time.If ever I get stuck in the bush with no recovery gear I would be happy as a pig in mud to find two such lengths of timber by the side of my car.
Peter