I actually got a nail in my tire the other day.. well discovered it I should say, I was probably driving around with it for weeks. I brought it to my dealer who is also my friend and they put a plug in it, but warned me its kind of dangerous, considering my hole was pretty close to the side wall (but on the tread).

Anyway as far as Sealant is confirmed, I don't know what you read, but I read (i think in the owners manual? or another document) that the sealant should only be used in a last attempt, because once you use it, the tire is done for. Your not supposed to use the tire after using the sealent, except for that one drive to the dealer/shop.

This is the impression I was under, which is why I didn't use the sealant. Sure, it could have added some protection for my drive to the dealer, considering I was doing 70+ on the highway.. but it would have made the tire unusable, and I wanted it fixed.