James63 wrote: "I don't get how you could go through the effort of making/buying great drivers and using a so so box."
If I can hazard a guess as to the direction you're coming from, there are two broad categories when it comes to speaker cabinets.
One is the Harbeth/Spendor/BBC approach which acknowledges the existence of the back wave of the speaker cone and sets out to do something to help dissipate it. Their practice is to make a very carefully crafted "lossy" cabinet that acts as a "crumple zone" would in a car crash to absorb a lot of that energy. The energy that is absorbed by the cabinet reduces the amount radiated into the room at frequencies where the ear is most sensitive.
The opposite approach is to make an ultra rigid cabinet. The one drawback to this approach is the speaker cone still produces a rear wave. This energy does not magically go away by itself. If the speaker designer doesn't do something with it, you can find that energy re-radiated back into the room through the driver's cone. Energy in the lower voice range is not well absorbed just by speaker stuffing so the designer has to think of other things to do with it.
Each approach - and the variants in between as well as dipole and other boxless designs - has its following, just like car enthusiasts or the subgroups that develop in any other hobby.
However, calling the Harbeth a "so-so box" ignores the extensive effort that went into the speaker as well as the philosophy behind it. It would be just as easy to look at any of the tall, narrow speakers that are popular these days and insulting their designers for complicating the baffle step effect for the sake of furniture fashion.