They are seen in the hills a lot because of reviews, "fashion" and availability in the shops rather than they are better than anything else.
Could you post the research you've seen to back that statement up please Lillian?
I know what you're trying to say, but you don't half have an argumentative way of saying it! What you describe as "fashion", as if those who buy them are just following the crowd, could also be described as "reputation". By your own argument no-one's going to buy an uncomfortable sack, so we must assume that all those followers of fashion (I'm one of them) actually do find the Osprey's to be better than others they've tried? If not, we really are a bunch of idiots aren't we!
I don't disagree with most of what you've said, just the way you've said it. Osprey have done a great job with their marketing, it's true, to the point where they tend to at least be on the shortlist for most people buying a sack, while others like Gregory aren't but should be, but that's not "fashion", it's good marketing, good reputation, and a product that justifies it.
It's certainly not true that a poor product won't get poor reviews because people won't buy it. Again I understand what you're saying; If it doesn't suit someone, they'll simply move on, but no, if they were actually uncomfortable there'd be blog posts and all sorts saying so. Some people will find them uncomfortable when they try them, like in the forum thread you linked to (having said you're unlikely to read of poor experiences?), and others will find them fine in the shop, but not once they get serious use on the trail. All of that will be reported, as it is for all types of products (the power of the internet eh?).
The fact that so many people report good experiences, so few report the opposite, and that such a large proportion have them and use them, does suggest that in general they should at least be on every shortlist. Yep, so should lots of others, and yep, they're all only any good if they suit
you, but nope, the fact that lots of people use something doesn't automatically make it a fashion.
I bought mine because it was at least as comfortable as the others I tried (Lowe Alpine, OMM, Deuter and Berghaus), but also had clever little features I like and will use. Not because I'm some kind of unthinking sheep, following fashion.
Today, SouthDowns is modelling a beautiful off the shoulder "Kestrel 38", in delicate fern green, with grey highlights that perfectly accentuate the tones reflected in his hair, styled today by Monsieur Dragfru Edgbacward. Note how the the hip belt cuts into his body, flattering his already perfect figure.
Cheers,
Slave to fashion.