I have a metcalf that I have used for many day hunts and packed in for multiple days at a time as well. Longest I've used the metcalf to pack in for was 5 days, went with a buddy who used a longbow. I'm amazed how much I can cram in that bag.
The metcalf works great compressed as a daypack, and I prefer to use small dry sacks to organize my gear within it. I also prefer a more minimalist setup, which the metcalf is. I think the longbow is a better daypack only bag, the internal pocketing and access are very helpful. If you value pocketing, longbow is a good call. If you value flexibility, the metcalf covers a wider range of situations. That depends on how much stuff you pack of course. One other thing to consider is packing heavy weight in the bag vs using the space between the frame and bag.....I've found the metcalf (with lift kit) helpful since I can do either, not sure how much meat you could cram in the longbow. Either way the lift kit really helps the frame perform; there isn't much load lift without it on the longbow.
My buddy packed in for 5 days with a longbow. He had all sorts of pockets strapped to that bag and slept in a bivy sack, and at times we thought it might explode, but it totally worked. So either would treat you well, just depends on what you prefer. Hopefully this gives you a couple things to consider. Let me know if you want to see any pics of the metcalf loaded up, compressed etc.
