I think the reason why folks don't have "high-efficiency" drivers in the average home market is because:

a)they like cute little cube speakers that sound just like "little POS", cosmetic looks are higher priiority than sound!

b)is because the higher efficiency speakers are more revealing of the sound sources, and that would show the inadequacies of their mainstream amps/recvrs which are mass produced across the great pond, compared to our SET's which are more costly than the entire "stereo-in-a-box" type systems(which include "cute little cubes" again).

c)decent high efficiency drivers usually cost more than the "made by the thousands" stuff across the great pond

d) most importantly you must understand that for "most" folks, the quality of audio is not a critical need. Only a few of us(me included) actually spend time dedicated to "audio only", sit in the perfect spot(the sweet spot), and spend money like I had it to burn(sometimes missing meals and other luxuries) to get the ultimate in sound reproduction according to what we think the best sound should be like.

My apologies in advance to the Bose and other fans who like the little cute cubes, but just remember, just like engines, there really is no substitute for cubic inches!!! Little speakers sound just like little speakers. You can't change the laws of physics.

Ron (fan of refrigerator sized speaker systems)