McCormack DNA-1 vs. Adcom GFA-5802

Relative noob here. I'm looking for a new (used) 2-channel amp to power my new Polk LSi9 bookshelf speakers. I've pretty much decided that I want to get the McCormack DNA-1. I've considered the Parasound Halo 23, as well as the Adcom GFA-5802, but it sounds like the McCormack DNA-1 is the better amp, according to a number of folks (unfortunately, I'm unable to personally listen to any of them).

My question is this: if the McCormack is the better amp, why is it priced around the same place as the Adcom and the Parasound in the current used market? I realize that the Adcom has a bit more power, and Parasound has made some great amps, but people seem pretty unanimous in preferring the DNA-1 for sound quality. What gives? Am I missing something? Is the used market just not as rational as I thought it would be, or has the superiority of the DNA-1 to the Adcom GFA-5802, and the Parasound Halo 23, been overstated? Is it just a matter of taste? Preference for the DNA-1 seemed to transcend mere fanboy-ism.

Thanks for any input.
Did you acquire the .5 deluxe that was listed? There is a 1 deluxe available as of today. Good-luck!
@Pbredi: I saw that .5 was gone very quickly after it was posted. Unfortunately, I'm not the person who grabbed it. I also saw the DNA-1 Deluxe...slightly above my pay grade at the moment.

However...I found a DNA-1 for ~$700 elsewhere (before the Deluxe was posted), and it'll be in the mail to me as soon as the check clears. It would have been nice to get the Deluxe; it would have saved me some money when I inevitably send it to Mr. McCormack for the B Revision (I think it's called Silver now). But I'm pretty happy with what I paid for the "standard" version (assuming it works). If things don't work out, I may come back to that Deluxe, if it's still available.
Cool! Don't look now but there is a .5 rev 1 that just came available. Oh, when it rains it pours. Enjoy this, it's so fun!
BTW, rev b or silver are just great. I have owned them.
That McCormack DNA.5 that had Rev 1 upgrade sure went fast. It looked a bit odd to me. I believe it had a serial # from McCormack of Virginia and the board said DNA-1 from the pictures. Normally when SMc Audio does a revisions there is a signature and date from Steve and or Kris. That I don't remember if the board on the inside of the DNA .5 says DNA-1. Well I hope whomever bought it enjoys it.
For those that are wondering this is straight from the SMc Audion wed site Q&A.

"The R1 circuit board was created by McCormack Audio to allow them to produce amplifiers from the remaining stock of DNA-1 parts, and to facilitate certain repair jobs where the original board had been damaged. This new circuit board is effectively equivalent to the circuitry in the DNA-225. McCormack Audio is now offering the “R1” board as an upgrade, including Cardas hardware and Noble emitter resistors. This makes a very nice improvement with a distinct performance advantage over the original amplifier.

Although the R1 upgrade is not connected with my work here at SMc Audio, some have asked how it compares to my upgrades. Direct comparisons are difficult, but I would say that it delivers performance roughly comparable to my Revision B.

I thought it was a good deal and no I didn't buy it.