how lomg should I smoke/cook baby backs

[Habanero Smoker]

As Gizmo stated you want to make sure you get rid of the membrane on the back. For ribs it is alright to leave the silver skin on (I believe that is surface connective tissue); so that will break down under low and slow cooking. If it was a roast, then you would think about removing the silver skin, because it will toughen up, and shrink.