I bought a CCO carrot cake on amazon a while back. I'm was not in love with the fact that it was incompatible with my '11 Ody jump seat so I bought a Marathon. I missed the return window so I still have it. I hate to regret selling because it's so darn precious, but not sure I will get much use. We fly next year to an island for a wedding, but other than that we don't do much traveling or transferring. Right now we have a FR85, TFP and MA 70 in our van and a spare TF in DH's car. He will be helping with shuffling children soon. Should I keep the CCO as a spare or sell and get a diff spare? How long do they typically last?