I have seen a couple warranty boards but not enough to wonder if they can hold up to the abuse riders can give it. I hit mine on rocks, sand, kickers, and rails and seems to be doing pretty good. If you have a dent in your rail you can sand it down and smooth it out to bring it back to life. Also sanding down those rails can lead to slowin your board and setting it deeper in the water and helps prevent catchin an edge on that rail.
The Flex and the construction of these boards hold up very well, but anything can happen out there so if you have an issue with your Slingshot products please contact our warranty dept and they will take care of you. Seriously!
http://buyslingshotsports.com/s.nl/sc.24/.f