How big is the s/m and the m/l. Both 40L? Don't see the description change with either one when selected? Is it a width sizing for shoulders?

Ignore the above - it is the size of the waistband and torso sizes that differ - see here - http://www.lengthytravel.com/my-latest-backpack-an-osprey-farpoint-series-review-40-55-70/#Farpoint_40_only

Heated and ordered - thanks OP - excellent price.

Most highly rated? Can you explain by whom?

Expired

I have an Osprey pack and their after sales has been amazing. I love my Aether, but I just have issues with people making unfounded statements like the above. I've been traveling for years and over the last few I've seen a lot of people with the larger version of this but no one with this size.I personally don't see the point of the features that this has on a pack of this size. The idea of traveling super-light and having a small pack is that you don't need to check it in on planes or buses, so why have the extra weight for the concealed harness and compromise on their support/comfort levels?

Agreed. It was between this and a Lowe Alpine (TT I think) at the time. There is the Lowe Alpine AT now though which looks good

http://www.amazon.co.uk/Lowe-Alpine-Backpack-Anthracite-Tangerine/dp/B00SHGU2NO/ref=sr_1_1?ie=UTF8&qid=1457462129&sr=8-1&keywords=lowe+alpine+tt

When I bought mine the Lowe Alpine model was apparently not as comfortable using it as a rucksac so I went for the Osprey. I use Osprey for general hiking and they are very robust - though I think Lowe Alpine are great too.

EDIT : looking at the Lowe Alpine I think the Osprey will still be more comfortable as the Lowe Alpine has no hip belt.

Totally see your point - I think some contributors use superlatives and misleading statements to get up votes without any thought of what they are actually saying. I got the Fairpoint 70 and have to say I was gobsmacked by the quality of it for a fairly low price. I am sure that if I had paid double or triple the price I could have got something as good quality if not better. But for what I needed it is ideal and would recommend the brand to anyone. This is a weird sized bag admittedly and your points are very valid regarding the weight increase to add the fold away bits etc. But I will just balance that out with my experience the last two times I have flown with Ryanair who were having trouble fitting everyone's bags on the plane so asked if anyone would allow their cabin luggage to go in the hold. I had a 25L Berghaus which had nothing of value in it so agreed and off it went on it's merry way to the hold. First time was great - second time one of the straps got ripped clean off. Got compo but thought it would be great to have the same option as my larger bag for just this eventuality again, so ordered this. Plus I like the strap option.

Well I guess having had a carry on bag damaged you've got a reason to aim for something more sturdy, so fair enough. But for most people I see the features on this as expensive overkill, it's VERY niche. Hope it works out for you

As mentioned - the concealed harness makes it more like a suitcase and less prone to getting caught up in anything. As for travelling super light - if you travel EasyJet there is no weight limit. I use vacuum bags to compress clothes and can get some weight in there. I think this is a robust option for those not too worried about being super-light. I went hiking in the Dolomites with this for 1 week and managed fine. If only they would let hiking poles in hand luggage though.