The DIY Marty builds can be very fulfilling, too. There is a very long thread over on AVS dedicated to the Marty Sub Concept. Your video is making me think of the Marty Subs.
Again, this all comes down to your values and what you want to achieve. Along with that... How much you are willing to spend to achieve it.
MDF out here on the West Coast is over $50 a sheet for 3/4" stock.
Sonotubes become an alluring option because of the cost and weight.