So guys, tell us all why it won't work then? Airspace is airspace correct? The strongest type of enclosure is a cylinder, correct? I see ports that appear to be able to be cut down in length if necessary as well, tunable = yes. If it is made out of ABS, aluminum or fibreglass, it is going to be stronger than mdf and lighter than mdf. This is all with me only looking at the pics posted on this thread and not visiting the site itself. Think outside of the box and what you consider the norm. Back 20 years ago almost a company named Bazooka came to the market with a tube sub, while it was not the best thing on the planet, it worked real good and as it was promised to. Look at the company that Bazooka is today. People have and do compete with their tubes and have yeilded good results over the years. Time to visit the site next.
FYI, the comments I read were exactly the same type of comments made when bandpass boxes hit the market. Those on the forum older than 30 years old might remember that. Those under, not a chance.