My favorite company is Eagle, as they are still made in the USA.
USA numba one, GI.

My main pack is a coyote Eagle 3 day. Both my brother and I have one.
I also have the maxpedition pygmy falcon, which is my main go-to bag for dauily or overnight useage. It is probably the best bang-for-the-buck pack I have.
I like it enough to also pick up an OD baby condor. I have not used it much, yet, except to tote around my loot at militaria and gun shows.

I have a couple of blackhawk packs, among them the phoenix. It is like a 4-5 day assault pack. With the add-on side pouches, it can hold a roo's worth of junk, for a 3 day trip during the winter. That's when weak roo's need lots of clothes to stay dry and warm, plus bigger rounds that go thru thicker things.