the 170 sleeps sideways- not only is the bed short but every evening visit to the head requires a climb over.
and i bet that width is closer to 72" ( that's the width of the bed in my PW Lexor on a Chev- at the mattress...and the sides of the van slope in slightly)
the 170 also has cabinetry from floor to ceiling and overhanging the bed.
I'd look at a larger model
a longer wheelbase van rides better and gives more space- 2 feet longer isn;t going to make a difference in parking or driving.
it will give a more open interior and a larger bed.
RT Verstile models are sideways sleepers, popular sleep fore/aft
I chose my model based on bed size, 72" wide and 75" long on the drivers side, 72 on the pass side
I much like my Pleasure-Way- a quality build- the RT models may have a drop floor section- I kept tripping on the transitions.
I can stand up fine in my van in sneakers, but not heeled boots.
my 2005 chev chassis is great, we have the 6.0, it gives about 16 mpg- the smaller 4.8 may not give better mpg as it will work harder - I think the 270 hp 4.8 marginal for that weight ( I have the 4,8 in my pick up).
you are likely to find the 4.8 in the RT170 and the 6.0 in the RT190 models
we were able to find a fair variety of rv's in our area between private parties and dealers- very helpful were videos on youtube posted by dealers- watch how easily ( or not) the big guys move around inside the vans
Mike