Aside from gliders, the only other composite aircraft I've flown have been the Diamond DA20 and DA40, both of which have temp activated disks on the seat bulkhead. the color changes when the inside temperature exceeds 131 degrees F. There are also placards stating the temperature limitations warning of possible structural failure if flown when the temp has been exceeded, granted they mean flying it if the aircraft is that hot. But still, if the manufacturer states there is a danger, there must be one. I know my POH in the gliders I've flown state temperature limitations, though I've not seen any fancy temp sensitive color turn tapes glued in the cockpit of any glider..