The one thing that scares me a little is the 333 Pounds on the RBH 21" sub!
Thank gods it's externally-powered!
The Magnetic Grille is 11 LBS. So the actual sub itself is about 322 LBS.
I guess maximum performance = extremely heavy cabinet + bracing for the monster 21" driver.
RBH says they will likely include a FREE DOLLY and probably make the wooden crate fold down and turn it into a Ramp.