I've owned five big danas - the real old one has cordura shoulder straps that are ergonomically fine but not super cush. No biggie. This one had the softest hipbelt reinforcing panel of the bunch, which isn't a good thing. Also, the open cell foam against your back rotted, and I pulled it out through a slit and replaced it with closed. Doesn't ventilate much, but no biggie. I'd wet out with sweat on a warm day either way.
The Mexican packs are great - light pile lined shoulder straps, and nice stiff hipbelt backing.
The firesale externals in '00 or so had the cheapest shoulder straps of the bunch. I spent 3.5 days straight under a dall sheep in that pack with no chafe or heat.
IOW, my experience does not line up with yours whatsoever. I move a Mexican large hipbelt between my danas now and it works great. The Mexican mediums do too, when I'm not fatty fatty 2x4.
