my armadillos are up to about 6,000 miles with no flats. I run a 700x32 up front with a 700x35 in the rear. I run the wider tire in the rear because when I am loaded up in touring mode; it's nice to have a little more give in the rear tire, and when commuting I drop the pressure down to give a little extra comfort.
As mentioned above, these tires are rugged as all get out, but ride like it. I don't plan on putting armadillos on my touring bike when the current set wears out simply because of ride quality, but my commuter will get more, it's hard to argue with such a tough tire for such a good price.