There are at least two things wrong with carrying a pack that is too big. First is that you will be tempted to "fill 'er up" and carry all kinds of things that you don't really need. Second is that what you do carry will end up in a lump at the bottom of a mostly empty pack. Third is that the pack itself will be heavier than it needs to be.
What I like about it is that it is a clean simple pack without frills. Mine is now sun faded, and the lower part that rests against my back is starting the tear and shred, but it is still going strong.
My main complaint about this pack is that the lid flops towards the rear of the pack (rear, being towards behind you if you are wearing the pack.) This has dumped its contents out unexpectedly countless times. All my other packs flop towards the wearer, and maybe I am just used to that.
This is my first pack from Deuter, which is a German manufacturer. They say they will repair or replace it forever. I was almost going to pass it by because of the panel entry zipper. I have always wanted a bulletproof "bag" with straps with no zipper to fail. It remains to be seen if the panel zip lets me down. They will repair it if it does, but I might still be out in the field with a busted pack and things falling out of it.
People compare Osprey to Deuter, and it seems to go as follows. Osprey packs have more frills and gimmicks and tend to be made of less sturdy fabrics. Deuter packs are simpler, cleaner, and more rugged. I think frills do sell a lot of packs, but not to me.
This is a 2 pound 10 ounce pack with a Delrin frame. The materials are stout, and I don't mind some extra weight for a daypack. I like the side zip pocket instead of a second place for a water bottle (If I want a lot of water, I will carry a hydration bladder). I also like the zip pocket on the hip belt. Yes, I suppose I am falling for some less than basic features.
Everything Arcteryx makes is phenomenal. You do pay for it, but you absolutely get what you pay for. I don't own one of these, but the Alpha FL has a good look about it. The letters "FL" are for "fast and light". 1 pound 4 ounces. That certainly is light, but they say it is for serious climbing.
I would pick the Alpha FL 30 over the Aerios 30 by Arcteryx. The Aerox has a wrap around hip belt and suspension that I think would just be a bit much for me. 2 pounds.
Tom's hiking pages / tom@mmto.org