First off I have to say that I absolutely love the concept of these park series bags from Big Agnes, and I think with a little work they would have a winner. They are extremely roomy, which is paramount for me as I just can't get comfy in a mummy bag, and the Summit Park is light enough to pack. But the 15 degree rating on this thing is WAY over rated.

I have now spent several nights in cold weather in this bag down to the mid 20's. Have tried multiple pads with this bag. Two inflatables and a prolite 4. The last 2 nights with an Exped Synmat 9 Deluxe rated at R-6 and approx 0 degrees. With it, a full fleece liner and a layer of Capilene 4 I was just barely comfortable on cold ground surrounded by snow with temps about 25.

The down in the bag seems to work it's way towards the edges more than it should. BA says that they have corrected this with a different baffle design but I have the new design and it hasn't. There needs to be more down over the top of the body and not around the sides. Seems that in a race to produce the lightest that they gave up on comfort. I would gladly pack another 8 oz of down that stayed in place in this thing in exchange for comfort.

Oh, and the zipper ALWAYS gets hung up.

I have spoken with BA and they are great to work with, but even they suggested a liner or heavier insulated pad. Which I already have. They also gave me the name of a company that can do alterations and add more down. What would you bet they have had this complaint before.

These companies really should be held accountable for putting out these ratings hence the 2 stars. This is a 35 degree or better bag and if it would have been advertised as such, with a good zipper, it would be 5 stars. I am using this with equipment that is designed for colder weather. We should not have to go to extremes to make their rating work. There is only one other warmer pad that I am aware of and that is the Exped 9 Deluxe Downmat with an R-8 rating. I may get one, or I may just not camp in 25 degree weather any more.

Can some one please produce a true cold weather bag 0 degrees or so that is roomy, packable and comfortable?

Warm weather it's great. But I just spent one night in the upper 30's on this thing. It is NOT for the 35 degree weather that it is rated for. Even with a layer of Capilene 3, pants, tee, heavy fleece, and a BA Summit Park 15 degree bag I froze. Would not use it again below 50 degrees or so at least with any Big Agnes bag without a closed cell pad. And then you might as well of had an insulated pad instead. Comfort, small roll up size, weight and durability get a 4.5 out of 5 though.

I purchased an Exped SynMat 9 Deluxe for the BA Summit Park and it rocks in colder weather. A little heavy, but a bigger comfy bag and pad are the two luxuries I refuse to compromise on.

Fantastic product. Does exactly what it's supposed to do. Quick boil, light weight, super small, wide adjustable flame, sturdy wide support. One of the better products in my pack.

I'm an outfitter in MT and have spent many nights in the wilderness. Needed to find a new solo tent for the high country. Used this tent one night and that was enough. Super light weight and extremely thin but seemingly tough enough material. Seems and stitching seem sound. Other than that I found it to be a poor design. Had a storm blow in and drop the snow level to my elevation and it rained, sleeted and blew all night. Temps about 35 degrees F.

It is not free standing and I found it impossible, either setting it up at home in good weather or especially after 8 miles and 4000 or so vertical feet in the cold, to guy wire it out correctly. Even with all the stakes.

Though the specs read that it should be able to fit the Big Agnes Park long series bags, it does not. There is no way to fit one and not have your feet rub against the lower end, which inevitably led to the lower end of my bag picking up a lot of moisture from the walls. I find it hard to believe that any normal sized human in any bag could not end up rubbing the walls. This thing is REAL small inside. I'm 6'1” and 225 lbs. Forget about sitting up.

Cold air also blows in on your head as there is no wall by your head, just mesh. Then every time you need get in and out of the fly water pours in all over your head as there is no way to open it up without that occurring because of the angle of the tiny vestibule. No way I was fitting my Gregory Baltoro 70 Lg, 4638 cu/inches in it either. Just enough room for shoes and maybe a very small pack and water bottle.

I like Big Agnes products, but this one missed the boat. I'll be getting a Copper Spur UL2 instead. Same material but big enough not to rub against. And room to store my pack. I'm willing to give up a bit of weight for comfort. The Fly Creek is maybe a fair weather small person no rain tent at best.