Size of Circuit vs Gorilla?

I have both packs and I can fit significantly more in the Circuit than the Gorrilla. The main difference for me is the extension collar is much bigger in the circuit, or at least more usable. I typically use my gorilla for 1-3 day trips in the spring, summer and early fall. I'll use the circuit for anything longer than 3days where I need more food, or for trips where I need more insulation. Both are great packs though. I probably use the gorilla more at this point though as its lighter and I don't need the volume of th circuit on most of my trips.

Thanks, that's kind of the impression I had. The Circuit seems like an ideal 'next size up' pack from the Gorilla. How about comparative load bearing?

I own a Medium Gorilla, and was looking for a larger volume pack for winter trips just last week. I thought about the Circuit and the SMD Fusion 65 as well as the Mariposa. I was seriously considering the Circuit though. I even went up to Mountain Crossings and tried the Circuit and Fusion on. The Circuit is larger than the Gorilla, but it's not a huge difference. So, I then realized that, if I love my Gorilla this much, why wouldn't I just get the Mariposa? They should fit and feel the same right? I was worried that the Mariposa wouldn't be that much larger than the Gorilla either, but I was pleasantly surprised to see that it was. I think a combo of Gorilla for 3 season with a Mariposa for winter is perfect. So, if you enjoy you're Gorilla, why not give the Mariposa a shot? You can use your Gorilla hip belt for the Mariposa saving you $35. Anyway, here's some comparison shots. Fully lofted quilts in each of them to show space. I can fit significantly more gear in the Mariposa. Not exactly what you asked but just another option to think about. I'm extremely happy about it.

My personal opinion is the Circuit carries weight much better than the Gorilla. For me, the circuit transfers the load better to my hips. The combination of a better hipbelt system and load lifters is a big part of that. The gorilla is also a little small on the torso for me and while I don't notice it when im carrying less than 20lbs, it becomes more noticeable on my shoulders above that. I just ordered a Zpack Arc Blast to give it a try. I didn't really need a new pack, but I like trying new gear and I wanted something with the load carrying abilities of th circuit at less weight than the gorilla. If the zpacks works out it migh replace the rest of my packs.

Since we’re talking about it, there’s a possible group buy on Massdrop, if enough people vote for it. I’m hoping it makes, so please go vote if you’re interested. Gossamer Gear Group Buy{/a}

Thanks – the Mariposa is a pack I've been considering. How does the new version compare to the previous? As for ZPacks, for me it'd have to be the Arc Haul. One of the reasons I'm favouring ULA is durability and I just don't trust cuben long term. So any pack I go for would need to be dyneema (preferably 210d) or robic. If money was no object I'd get a custom pack made by Jep Paks – to me the perfect solution: lightweight, durable, combined removable stay and pad sleeve, great storage options and comfortable. But beyond my budget. Re. Massdrop – the link didn't work for me.

Just to throw another comparison into the mix, how does the Ohm 2.0 compare to the Gorilla (2013 dyneema) in size and carry? Pretty similar in size I'd have thought?

I just got the Mariposa and haven't used it or seen previous versions in person, so I can't really comment on it yet. I do know that the robic used on it is tough stuff. My robic gorilla looks brand new after dragging it through miles of dead fall. So no worries on durability from me. Gorilla v Ohm 2.0 IMO these packs are in the same category. Volume and max carry weight are pretty identical. (I know a lot of people will disagree one way or another.) In my eye, these two packs are direct competition to one another. If you need more volume, the Ohm isn't the right choice. I didn't like the Circuit because of the tapered bottom. I know it's one of the most used packs for thru hiking because of the perfect balance it achieves with durability, features, weight, and carry, but it just wasn't for me. If you have the ability, order up the packs you want to try out and send back the ones you don't pick. You can't really do this with the Arc Haul though. If I had the money and the patience, I would've gone with an Arc Haul myself. I'm very happy with the Mariposa though and it carries my winter kit perfect. Good luck on the search.