nunatak Arc Ghost vs Rab Quantum Top Bag

The Arc X Specialist is a good alt. to the ghost. It has three straps, better down control and other updated features. I have one and love it. The third strap is a definite advantage over the ghost’s two. Best, Jhaura

I do not know if they changed the design any, but I had a Rab Top bag about 4 years ago. In my opinion, the design had a major flaw. There simply was not enough "bag" in the lower section by the legs to block drafts. You had to insert a cut-to-shape foam bad to seal the edges, and this was very restrictive. I froze at around freezing in it. Maybe if they would have more bag and less netting or whatever is on the bottom now, it would wrap the body enough to block drafts.
I have no experience with the Arc stuff, whenever I use my mummy bags as quilts to try to simulate the concept, I get cold and zip up…

I have used a RAB elite top bag for a couple of years down to around 30 F. The temp rating IMO is not accurate. It should be considered a 40 F bag for comfort. I think a better buy is a Western Mountaineering Highlight, 35 F rated.

If your goal is to save weight and maximize warmth, then I would go with the Ghost. It's smaller than the Specialist so you can stay warmer (less space for your body to heat). If your going to layer up, then get the Specialist. The extra width allows for layering up on colder nights, or for going into shoulder seasons. I find that the Ghost is large enough for me to put on some extra layers of clothing provided that they are thin: Patagonia Micro Puff Pants and Montbell Thermawrap Jacket (I'm skinny).

You can order a third strap on the Ghost, it only costs $5.00 extra.

The Ghost also has an extra 1/4 inch baffle height. More loft, warmer bag. I have 1 oz over fill on mine, seems more comfortable to me and maximizes loft while controlling slump (not a side sleeper, so not usually a problem). Over fill should also help the bag loft better with the heavier Epic fabric as opposed to the standard .85 fabric.

If your really intrested in the Ghost or Specialist you should call Nunatak, Tom has better info on these bags than I do. He's a really nice guy and very helpful. He answered all of my stupid questions without making me feel dumb (even though I am).