The owner had his rig that is for sale at an RV show in Portland a few years ago, we drove down to look at it. The workmanship & cabinetry seemed very good, The interior was beautiful. I did not like the entry way at all, had to open a compartment and pull out a landing and stair way to access the coach door. Looked more like a set up for a trade show vehicle than an RV.
At 53 feet long it exceeds the length limit for a straight (single) vehicle in a lot of states. Plus you are not getting it in most campgrounds. perhaps not a problem if you stay in big open campgrounds or at a racetrack.
He does have an unusual means of dealing with the length in tight places. There are a set of hydraulic jack legs with small powered wheels that drop down in the rear and will drive the back end of rig sideways. (I would worry about the small contact area of these wheels sinking into soft asphalt with the weight of the rig)
As powerhouse only builds on Volvo chassis along with some of items above we decided that they were not the builder of choice for us.