Ok, this is a shameless plug, but the comments are true. Disclaimer - I am currently selling this;
http://cgi.audiogon.com/cgi-bin/cl.pl?preatran&1171971732&item
I have recently tried the K-5xe with my DNA 500 and thought it performed very well. You are correct, the impedance is a perfect match even with the lowish input impedance of the DNA 500 (10k ohm). In addition, the ergonomics are excellent and match perfectly with my CX-7e cd player. The blue/purple light is very nice looking and casework is top notch. The sound with my McCormack was clean and musical with good bass punch. The only reason I am not keeping it is that I just can't bring myself to give up the sound of my $7,000+ Atma-Sphere MP-3. I sure will miss the ease of use of the K-5xe though. I was able to use only one remote for both the K-5xe and my CX-7e, and the appearance of both units mate perfectly. In fact, if you would be interested in both the CX-7e and K-5xe let me know since I have some gain matching issues with the cd player and my MP-3 so I am thinking of trying a different player. Both units are in excellent condition.
http://cgi.audiogon.com/cgi-bin/cl.pl?preatran&1171971732&item
I have recently tried the K-5xe with my DNA 500 and thought it performed very well. You are correct, the impedance is a perfect match even with the lowish input impedance of the DNA 500 (10k ohm). In addition, the ergonomics are excellent and match perfectly with my CX-7e cd player. The blue/purple light is very nice looking and casework is top notch. The sound with my McCormack was clean and musical with good bass punch. The only reason I am not keeping it is that I just can't bring myself to give up the sound of my $7,000+ Atma-Sphere MP-3. I sure will miss the ease of use of the K-5xe though. I was able to use only one remote for both the K-5xe and my CX-7e, and the appearance of both units mate perfectly. In fact, if you would be interested in both the CX-7e and K-5xe let me know since I have some gain matching issues with the cd player and my MP-3 so I am thinking of trying a different player. Both units are in excellent condition.