I was told by an Odyssey dealer that the life of the PC625 is 4 years with free replacement if there is any trouble before that time.  Also, I was told that that battery could be recharged 400 times---I don't know if I believe that, however.  I have two PC625 in my plane---I tried to put one in my P28/160 but was told that it would void my insurance (I did put it in and the plane never started so easy)  I mut the concoed in and I always wonder if it will start--on a cold morning 60 degrees F I still need to jump it.

Your second question--my 360 is carbon fiber--my son's older 200 is fiberglass--I paid extra to get my kit in carbon fiber.

Paul Hershorin