Unfortunately your not going to find the "ultimate sleeping bag" under $180 bucks. A sleeping bag should be considered an investment. I'm not saying you have to spend tons of money, but as one of the most essential pieces of gear you will ever own, it should be placed high on the priority list.

A sleeping bag will either make or break your trip (comfort and warmth), will be the item which will save you the most weight or weigh your pack down the most, will last you 20+ years (quality down bag) or as little as 3 years (cheap synthetic), and will be the item that gets you excited to get out or will be the item that causes you to never want to backpack again. It is in my "holy grail" category (pack, tent, sleeping bag, pad). You buy quality here and they will last a lifetime.

I would stick with down if at all possible because they give you much more value than even the best synthetics. Down bags compress smaller, last significantly longer, are far more comfortable, but are more expensive. I've owned several Polarguard bags and they have a life of about 10 years max. before losing all loft. Any other type of synthetic fill will last about 5 years or less.

My suggestion would be the Marmot Sawtooth as a starting point (retails for around $200.00). You get an excellent bag, 600 fill down, the best hood IMO, a temp rating of 20 degrees, and reasonable weight and packability. Kelty down bags are ok, but lack the proper fit, construction, and are often not as warm as they claim. However, if it's between a Kelty down bag and any other synthetic I would go with Kelty. My only other suggestion would to keep my eyes open and be patient looking for a deal. Steep and Cheap have had decent down bags, most recently (a couple of days ago) a Big Agnes down bag and pad, retailing for around $350 for $170. Sierra Trading Post also have options, but I would be concerned in how they fit. Often there is a reason why they are on closeout.

My 2 cents.
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