Re: Eberlestock users -- opinions...
I have used the J107 for a couple years. It's a great pack with plenty of adjustment, both in the waist and the shoulder height. I don't use a Harris, but yours should fit just fine.
When you are in the market, give the guys at the Outdoorsmans a call (800-291-8065). They carry Eberlestock, as well as Badlands, and they designed their own external-frame pack that wears like an internal-frame pack.