I'll pass on that. I originally specified the U series because they are on sale @pre order prices. I might go with a pair of u 12 D4's.
One thing I don't understand is port sizes. When I received my X10 box, I assumed I would have a 2x12 port (random number for visual idea) and instead I had a 2x2. I asked around and was told the port sounds about right for the box, tune blah blah.
Are the large ports just visual or does it actually benefit the listener?
Is there a preferred port type for low and loud?