Recently I went shopping around for polk TSI floorstanding bargains. I tried to listen for the difference between the 300 and 400. In the same listening room was a pair of energy cf30. At my request, the dude hooked it up for me. After listening to the polks, this small energy floorstander sounded superior. The 'T' did not sound like an 'S'. It wasn't that ear bleed inducing tweeter from a taxi. Whether or not they are 3k better, as the price suggests, I'm not sure. Even the bass area was more tighter and deeper on the energys. Its at that point that I felt like I should have brought my own music cos even the energys couldn't make Judy Boucher sound like an artist. What shocked me most was that polks 400 had 3 drivers and energy only two yet the sound stage was slightly more expansive on the energys. I thoroughly enjoyed those speakers and they were playing off the same equipment I have at home.