Unless your in Southern Utah and its 100 degrees. Everywhere else and just a slight breeze will cool down your backside and make you uncomfortable.

Sleeping pad or underquilt, you really only need one or the other. Pads are a pain but they get the job done. I are my pads for a couple if years, and finally was able to get an underquilt.

Underquilts are so much easier to get a comfortable sleep with. If you think you might want one, then the answer is yes, you actually need one.

The best value out there is the Arrowhead Jarbridge 3 season synthetic. If you want to open your budget a bit, the Hammock Gear Econ underquilt is the best value for down. Both are awesome companies that I've bought from and are small cottage shops that deserve the business.