They're emphatically not cheap, but the various Berthoud bags (scroll down) are generally well-reviewed in the rando community.
I've got the V-O bag, with the integrated decaleur; pretty decent bag, but I found it slid side-to-side more than I liked when heavily loaded, unless I strapped it to the rack underneath as well, hence negating the quick-release value.
2012-01-16 17:28:17