First UL pack…

Not a Kumo user, but I have some experience with MLD Core and Zpacks Zero. I like hipbelts on just about everything, including my REI Flash 22, because they keep the load from swaying when walking fast, and from flopping over when scrambling… leaning to reach hand- and footholds on rocks/root/trees. Nothing more annoying than stuff flopping around. Only gotten up to 16lbs or so with the Zero and found it quite comfortable. I agree that the wider shoulder straps are helpful in this regard, although the simple nylon webbing hipbelt helped more with load transfer than I had expected. One thing, my back gets a lot wetter from perspiration with the frameless packs compared to the Arc Blast or Arc Haul.

Have you looked at the MLD 'Burn'? Same c.i. as the 'Kumo' and weighs 11.75oz

I will second the MLD Burn recommendation. I think under 20 pounds is fine for no hipbelt, if you are closer to 16 then I say no problem. You can order the Burn with a removable webbing only hipbelt. Mine without hipbelt weighs 10.4oz. And you can't beat MLD quality.

Scott, Chad – Thanks for your recommendation. I've got a couple small MLD pieces and I have been very happy with the quality and functionality. I'll look at the Burn.

A couple more thoughts on the Burn, if you order it stock it comes with a hipbelt that has unpadded wings. I don't really understand the purpose of that design, so I went with the removable belt. It's nice having the option to use it or not. If you go without the hipbelt and are worried about stability, you could always try adding a second sternum strap. The shoulder straps are well padded and have a decent width as well as more of an S shape than traditional J. The shoulder straps are a major improvement over what was offered a couple years ago. Also the roll top is a nice change. Personal preference and all but it's what I like. So if you are coming from a Circuit, is the smaller volume of the Burn/Kumo going to work for you?

Good Q about the volume. My Circuit is nowhere close to full, particularly since I started carrying my TT Notch under the top strap. Most of my trips are 1–2 nights. I just don't need much stuff with me. I'm in no rush to ditch the Circuit. I've carried my load + my wife's on the rare occasion she joins boy and I. Also I'll keep the Circuit for when my son and I return to the Sierra Nevada or if I go to Philmont with him. The point is I'll have the ULA around if I need volume on a particular trip. Edit: I started another thread in Gear about this topic. Over there the conversation went to trying out my Circuit without the stay or hipbelt. I'll try that out day hiking this weekend as an experiment.

I ordered a ULA CDT without a hip belt for my frameless pack. ULA fits me and I have been real happy with my Ohm for everything else for quite some time. I had a Circuit. My problem with it was that I always filled it.

Are you guys telling me I could have ordered a new Burn pack without the hip belt? In the past whenever I asked MLD about a custom pack option I was always told sorry no. So I ordered a Wasabi burn..but I just returned it back today because I could not use it comfortably with the hip belt. I wanted to try the pack for my winter gear, but the hip belt was the deal breaker for me and I sent it back today. For 3 seasons I have been using Gossamer Gear Murmur Hyperlight pack (not the newest one), and I have loved it. My last trip I went on a few weeks ago, I tried MLD Core pack. Yes, I fell in love with the Core pack and it will probably be my new 3 season pack.

Yup, I ordered mine with a removable webbing only belt.

Really you guys are talking SUL and should post on that page. Those guys have good advice for the very specialized gear you'll need. If you are talking total pack weights low enough to qualify for a "frameless" pack it falls, IMEO (In My Experienced Opinion) under the SUL category. Of course if you are talking about frameless pack weights of 25 lbs. and up then you need a separate page labelled, say, "MASOCHISTIC UL BACKPACKING". ;O)

I like the roll-top closure. It holds the burrito frame in place very well. ;-) In the end I think most of these packs are pretty similar. Essentially they are all stuff sacks with shoulder straps. So I looked at the shape of the straps, material of the pack and was lucky to discover that the roll top was helpful. I ended up with a Zero because it can be waterproof and the shoulder straps looked very comfortable ("S" shaped). I agree that well shaped shoulder straps are nice. I think most packs have good straps. Essentially I was sold on the waterproofness of cuben. I haven't used the pack long enough to determine if that was wise. I am very happy with the pack so far. Edited 2 add: the most important decision I made about the pack was sizing. That alone made for good weight distribution and transfer.

EDIT: Didn't realize this already got addressed in the thread… oh well. Worth repeating I guess. There's really only way to answer this question, because it's so personal. Load up the Circuit with 16 pounds and go for a long dayhike with the hipbelt unstrapped (or better, strapped backwards around the pack so that it's out of the way). I personally would prefer a hipbelt at 16 pounds, but many people won't. You'll never know without trying it.

I have a Burn and Prophet without hip belts. I used the Prophet on the PCT which was almost always less than 20lbs. 16lbs and below is pretty dreamy. I don't miss hip belts at that weight at all.