Headed off to an outdoor shop acrooss the mountain in Harrisonburg and a guy who seemed to know what he was talking about with regards to packs. Looked at the Mountainsmith he had in stock, didn't fit me right. Looked at the Deuter - too small a capacity. Decided to try the Osprey Ariel 65 and he suggesed a more heavy duty Luna hip belt for it after I described my lumbar symptoms. Got the pack home, loaded it up. Walked a few miles. Had some back trouble but decided it was due to the new pack. Went out the next day with it loaded. Pressed right on the lumbar. Began to have the familiar lumbar pain and nerve down the leg. Adjusted the pack here and there. No go.
So that cuts out Osprey, Gregory, Lowe Hyperlight and other models I did see that didn't fit or didn't have the capacity (at least 3800). Unfortunately most outdoor shops don't have a wide selection and in the size I need (small size pack for torso length, medium hip belt). As it is this guy had to special order the Osprey pack for me. At least I can return it.
Now am looking more and more at my "clunker" ie "blessing" - my Lowe Alpamayo 6 1/2 lb pack, small which happens to have a medium hip belt on it, that was given to me several years ago. I may need to foot 2 extra lbs for the ol' lumbar not to act up.
So be it. But I still have my eye open.