I've got the CT spirals in my Jeeps(3 in total). I buy them mostly for the convince and the warranty. I exchanged two now under warranty. No fuss just walk in to any CT plunk it down and walk out with a new one. They even keep the warranty in the computer now so if I lose the receipt its no big deal, they still honor it.
Both times were my own fault. I have a slow draw somewhere on my Jeep. Not a big deal if it gets driven every week but lately its been sitting for 3-6months between runs.