I just ordered a Catalyst for my BMT trip this spring. Its gonna be a big pack for me, but there will be some long sections between re-supply in the itenarary (spell check that). I was able to do a five day trip using an Atmos 50 this past summer with room to spare. But it will be cooler and weather may be rainy so I want a comfortable shelter and clothes to change into. But when I go on my regular 2-3 day trips this pack will be overkill. I still want to carry it cause I just paid for it. The Catalyst will make it easier to haul the dogs food, but there is gonna be a bunch of room left in the pack.

I loaded and tried on a Circuit, but it not feel much, if any bigger than the Jam2. Thats why I went with the Catalyst.

The pack should be here soon - so look for a product review and some pics.