I've just returned from an archaeological survey in the Umatilla mountains, 45 days of rustic tent camping. Brought the BGB hardcover with me. During that time, we went through two thunderstorms. The temperatures ranged from 50° to 90°f. At one point, the book was left inside a locked car with internal temperatures into 100°F. It remains solid, flat, with minimal to no page wrinkling. A copy of Pathfinder came along, a famously high quality product, and its pages are still wrinkled from humidity. While I still think my old 5th edition bluecover CoC is higher quality, the BGB hardcover is super solid.
Peasant's Crown... GRRM inspired BGB
Hauver, a magically anachronistic Victorian setting using Gaslight
Bear Tribe... Bronze age barbarian RQ6