We bought our 17Z back in 2010 and love our little mighty might camper. When we camp, we're pretty basic people and don't really need a big house on wheels. Unless it's raining, we don't spend a ton of time inside anyway. We love that the 17z comes with both a couch and a dinette which most in this size don't have.
We do use everything in the camper, including the shower so we don't want to store stuff in there.
I did make a couple storage mods. It's only the two of us so I made openings and doors under the dinette seats and we each have one for cloths storage. It's kind of surprising how much we can fit in each one.
I also made drawers in one cabinet under the sing for utensils and put shelves in all of the upper cabinets. Here's a couple pictures.
clothes storage
Utensil drawers
Ray