I jumped on each of these. The 176T is an amazing floor plan but I do have some concerns about what these are going to be priced at. The 176T is going to get up there on price.
The rear fold out bunk is on gas shocks, once you begin to lift the shocks take over so there is no concern about the weight of the spare tire. That also free's up the class 2 hitch on the back for a nice back rack. There are 2 support poles that are attached, they simply fold down, so you do not loose them or wonder what pole goes were. Similar to the pole system of a fleetwood pop-up.
The air mattress was a nice touch versus the traditional hybrid mattress. It will stow very easy, but you can also NOT put the bed out, and blow the mattress up for extra comfort on top of the dinette bed.
The 176t is the perfect floor plan for a family of 3-4. There are bunk-beds and a dinette bed. So you do not have to fold out at all, but lets say your kids have friends, cousins, grand-parents that want to come along, BAM you fold out and now you can sleep even more!!!