I live and camp in Colorado at 9,000 ft. My dog loves it!
I have camped with tents and hammocks for a long time in the high rockies of Colorado. When I got a dog a few years ago, I wanted to make sure he would be warm at night since temperatures can really drop. As I did my research for the best option it became clear he needed the Ruffwear sleeping bag. And he absolutely loves it. It is durable, easy to get them in, and packs down nice for backpacking. Me and Bubba-Blue the 100lb Lab approve and highly recommend.