I've had a 2005 Enduro since, well 2005. I've been through three chainstays and all have been warrantied with no problem. Now, having just stripped the frame down for a good clean (hmm, wasn't this highlighted as the issue in the Cotic frame breaking thread?) I have discovered another crack, this time in the main frame, on one of the ribs of the seat tube.
But because Spesh are a decent company with a lifetime warranty for the original owner, they're replacing the frame without any quibbles. I shall be getting a new 2010 replacement some time next week.
So two things to learn from this. One - lifetime warranties are definitely the way forward and two - always, always, always hold onto the original receipt.