I have gate- (valet-) checked my gear literally hundreds of times, since I fly out of an airport that has relatively few "big" planes. Whether or not it's heated, the gear has survived it. That includes gear such as a D100 and 18-55VR as well as a D3 and 400/f2.8. If it goes that way it is in a fairly durable ThinkTank International bag, but that's no different temperature-wise than any other bag after 15 minutes.
_____ Brian... a bicoastal Nikonian and Team Member
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