Went to Montana for a family reunion a couple weeks ago and had the Martin D18 out for at least a couple hours a day. The weather was hot, 90 degree + everyday and the bugs were terrible. The only way to cope with the bugs (no-see-ums in Montana) was to use repelant. Thought nothing of it at the time, but after getting home to Washington I noticed what was "sweaty stains" or something like that on the top and side where you arm rests. It didn't clean off. Bug repelant EATS factory nitro finish! Be carefull with your many dollar instruments outside. I wanted to cry at first... this thing was $3K. But I got over it as I didn't pay for a museum piece, I paid for the sound and the name. Lesson learned.