I found what I believe to be the cheapest source on the internet for these components, which is
http://www.woofersetc.com at $329 a set. I just ordered my two pair.
As for a review, there are several floating around out there. However, let me briefly share my own experience. I have recently listened to one set of these components, stacked up against Polk MoMo's, Infinity 605cs, and so on, running on 170W RMS per channel.
Every component set I just listed eventually began to crack under too much wattage, which is not unreasonable to expect. Most of them sounded good, although I had hoped for better from the MoMo’s, but the Diamonds simply went FAR beyond anything else on power-handling and clarity. They simply would not break or distort (although I’m sure it’s possible at some level of wattage that most would consider extreme for a 6.5” component set) and the clarity never changed at high volume. On top of that, I could detect absolutely no shift in the highs or lows with power increase, like most all comparable speakers will exhibit.
I wouldn't even insult these speakers by playing an MP3 or using a sub-standard head unit/amp. Trying my own CDs, I could hear sounds in the music that I didn't even know were there, in the past.
I give them 5 stars for both clarity and power-handling. I cancelled an order I had for Infinitys and went from spending $225 to $685, just because I liked them that much. They are truly incredible speakers and I doubt there is much on the market that can touch them. The price felt like I was giving blood but if only the absolute best will do, I guarantee you that these are the right choice. They are simply phenomenal.
At the 175-190W RMS x 4 that I will be running, I'm sure these will be louder than any rational human being would ever want to listen to.