Thanks Mike. Flight, as you say, offers a lot for 2-3 extra ozs: capacity, upper limit, barrel-resistance, water resistance (although Ohm can now be bought in xpac), some ventilation.
I’ve found that free pelvic & shoulder movement is the most important pack character for me. Currently using an old Black Diamond pack with pivoting belt and sliding shoulder straps for most trips. But it has poor volume/weight and the belt sags under moderate load (as Will Reitveld pointed out in his BPL review long ago). Looking for something bigger, lighter and nearly as articulated. Flight might be it.