Actually, as far as structure goes I have been told that they build a very good motorhome. (This is from a few industry insiders I have spoken to on Optima)
They are still pretty new at this and I do see some things that need some refining, but I have also seen some really cool feature they are using that no one else is. I know they build some great trailers so as far as the structure is concerned I don't think you have to worry.
They seem to have a specific interior that they use for most of the coaches so I am not sure on how flexible they are with customizing.
Best advice check a rig out in person, if you like it, be sure to visit the factory and get a complete picture of what you are getting.
I truly believe that with these custom built rigs, you have to really like to gamble with your money if you don't visit the factory that is going to or did build the rig you intend to buy.
2012 Showhauler 28'6" Motorhome on a Columbia w/ 450 Mercedes.