had our TT for 3 years now, and decided against using a cover. i live near Chicago, so we see some pretty cold weather and sometimes a good amount of snow. maybe i was sold some BS, but on purchase we upgraded to a 5yr warranty which included "ResistAll" treatment. supposed to protect from UV damage and other elements. after 3 years now, no graphic fading/peeling, exterior still looks like new. I do have wheel covers and a spare tire cover. Otherwise I just leave it out in the elements. I remember reading on these forums the last time this topic came up, the dealers store them all on outside lots without covers. Not judging those who choose to cover, but I decided it's not for me.