I LOVE my theracane. The things is amazing for any type of upper body tightness. I usually use mine 2-3 times a week and hit everything... it work great on you lower and upper back, pecs, delts, biceps, forearms and neck.
I would get this over the back knobber, as the theracane has some small nubbs on it that work great on the bi's and forearms that the back knobber doesnt have. I dont think I could live without my theracane anymore as it has helped so much. A theracane and a softball are the perfect combo to keep your whole body loose and injury free.