Only when I'm delivering pianos up there. Which isn't very often.
As for how the old ones preform. I had 2 in 8 cubes net each tuned to 29-30 hz. They lacked low end (probably partially due to the way it was loaded, ports and subs facing up), but it was there enough for hair tricks. Not only did it get very loud, it sounded decent also. After months of listening to it, it really started to show what lacked and what was strong. The new subs are completely different, and the new box will be completely different also. Basically an entirely new setup.