Matters the use for the trip and what you may use it for in the future. How cold will it be in the bunk house? Will it get wet on the way or inside the bunk house?

Most sleepings bags that are for backpacking and such will be great but the temp rating and fill may prove to be important.

I doubt you will need a bag rated -25 in a bunk house but call them and ask them. Do you plan on using it camping here in bama on a 15-20 degree or lower night? If not then you can get by with O to +20.

Fill is important. Down is usually best but if it gets wet its worthless. A little snow ain't gonna get it wet on the way to the bunk house if packed well. Synthetic has come a long way and is still warm if it gets wet.....but it ain't down.

The temp ratings are not absolute. I've about froze to death (not literally but damn sure uncomfortable) at or 5 degrees above both 0 and +20 bags. So if they were to say hey, it will get to 5 degrees in the bunk house (not likely), then -20 degree rated bag would be the ticket.

Good bags include but by are no means limited to: Kelty, Marmot, Mammutt, North Face, Big Agnes, Sierra Designs, Mountain Hardwear, ect. Store brands like REI are decent too for someone who isn't going to use it 30+ nights a year.

Call and get some intel on the bunk house situation, as in heated or not!

Just my opinion......but I usually do spend 30+ nights a year in a sleeping bag, in many different environments, in many states.