I purchased an 89RB back in February, it's been good to me. I have the comfort step and it is awesome but if you tow all the time you may not like it. I've not even towed yet (long story) but I'm hoping I could jacknife the trailer enough to still be able to drop the step. It certainly does require a longer extension, the comfort step itself is 18" wide and it's 21" including the step brackets. We've found it very useful as a small deck and I even find myself sitting on it quite often.
I'll personally never have a camper with scissor steps again. even on my last camper I through them away and used a little giant step ladder.
The super step is just the square tubing (4" maybe) with a single fold down step so it would definately be better for towing.
I guess it depends on how much you tow.