I've got both the vac formed version and the older GRP hull that was made a long time ago.
The former sits in the corner, I made some modifications to convert it to a cylinder based pressure hull. Then by chance I was offered an original GRP hulled version. This was much better, but it needed a heck of a lot of work. The hull was a very thickly moulded affair. I moulded some new 'skids' for it, and spent a lot of time with polyester filler getting the top hatch to fit well.
I've made up some new control surfaces from epoxy glass sheet, and then rain stopped play when I was unable to find small enough bevel gears for the side thrusters (trying to get this model as close to the real Deep Quest as possible). Anyway I've found some now, so I'll be back fiddling with it again.
I also made a small acrylic cylinder to go inside, instead of the dry hull arrangement used originally.