@Ari 

"Rocky Mountains" covers a lot of territory and you don't mention your activities.  Will you be car camping or backpacking.  What temperatures will you experience?  Looking beyond this summer, how will you use this equipment?

Good equipment costs money and this is especially true of quality sleeping bags.  You will spend a few hundred for a top quality bag and it will be money wisely invested.  If you are just car camping, bags will weigh more for equivalent warmth and can cost less.

I would recommend a mummy style bag rated to a comfort rating of 20 degrees.  For backpacing, it should weigh no more than three pounds, and preferably less.  Probably will have down fill.

Sleeping pad - I recommend a closed cell foam pad.  combine with an inflatable air mattress if you like.

 

Lots of

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