I have the Simms Ultra Light wading boot. Had them for a couple of years when the whole sole started to separate from the boot upper (right at the bend)
I took them to Western Rivers (the dealer here) and for $30. they sent them back and about 3 weeks later I had not only a new pair, but the updated version. Have been using them for 5 years since with no problem.
I have heard that the warranty is not that easy anymore, but there are some people out there that have abused it so badly, that we all pay.
Another instance of this is Orvis warranty on their reels. People are buying them and using them for a year and returning them for money back or a different model, when obviously there was nothing wrong with it.
I read people posting this act all the time.