I used my Bernina for anything thick. If I can get it under the foot, it will sew thru it. I only use my featherweight for piecing and basics stuff. I'm not sure I'd try anything too thick with it.
The hump jumper is indispensable for me. I hem jeans for my husband a lot and even the Bernina bogs down a bit when it comes to the flat felled side seams. Hump jumper works great.