Has anyone used this pack and is it any good in terms of size/capacity/comfort?

Fly Fishing Backpack / Safe Passage Tri-Pack -- Orvis UK

I see a khaki coloured version is recently out in the U.S. If I were to buy one, I reckon I'd wait until the khaki is available in this country.

Fly Fishing Backpack / Safe Passage® Tri-Pack -- Orvis

I had the old green/grey one which I liked but was a bit small to hold a drink and sarnies for a full days fishing. Got the red/grey tri pack which is slightly better and bigger, holds a couple of pint alloy bottles in the side rod tube holders. Has capacity for a camal pack inside but not supplied. Some nice touches like the concealed magnets to hold forceps and clippers etc but is a bit bigger than the first green/grey one.
The new green one is out now,I got my tri pac off a lad who works in shop as he was getting the new colour. Better than a rucksack but not as mobile as a vest, depends what you need it for. If you try your "luck" you could get the old colour half price at your nearest store when new colour arrives