Product review (3 stars): Could be worse, .............could be better..
I installed one of these about 6 years ago.  It is pretty powerful and provided good service until about a year ago.  About  a year ago we started having issues with the switch, (aka it stopped working)  to their credit zephyr sent another one @ NC. It cost $200 to install and worked "ok"
A few days ago the left fan motor bearing  gave up, overheated and screeched to a halt.  I figure that 6 years use with the original cost of ~~ $600 plus $200 repair this cost about $130/year.  I don't know that compares to other brands at other prices.  We are locked in to buying another due to vent locations,....etc.  Could be worse, .............could be better.. for what it's worth Zephyr service was fairly decent.