I have the 0 degree and 15. I took the zero with me on a late season elk hunt and it performed well. Temps got down into the teens most nights if not colder. I am 6'2" 210 pounds and never felt cramped or confined in the bag. It is roomy in the shoulders and feet. I have a rei brand mummy bag...
I tried out the Stone Glacier but found I didn't like how high it sat on my back. The fit and finish was great but wasn't comfortable for me. I switched to the Marsupial gear and am looking forward to putting it through its paces this year.
2018 Tundra with 60k miles and no issues. Mine is leveled and I average 14 MPG. As everyone has said the mileage stinks but I love the truck.
Depending on where you live I would recommend getting a catalytic converter theft shield. They are easily accessible from underneath and it takes about 30...