The 7NT's are nice but then we are comparing apples to oranges. The 7's are 2 1/2 way crossover design and lack in the complete seperation of mid and woofer. The 604 S3 offers nautilus technology with an internal tube mount tweeter enclosure and offers a 3 way crossover. The 9NT's would be the equivalent of the 604 S3 with 3 way crossover for twice the money for a very similar sound. The CDM series simply cuts the cabinet and partially exposes the nautilus design tube mounted tweeter. The 604's and an LCR 600 cost me $1672 - The 9NT's with the timbre matched CDM CNT would more than double the cost for the benefit of a "PARTIAL" exterior mounted tweeter and the CDM center offers only 1 mid/bass driver. The 604's are a much better buy at half the cost. The next step that makes sense would be the 800 series or even the Prestige (True complete nautilus technology) if you have a thick wallet my friend. The whole line, no doubt, is awsome! Listen and judge for yourself. Some people like a 2-way verses a 3-way speaker.