No dealers carried any DAC's other than Wadias, which started around 7000 dollars. So there was no opportunity to do so unless I wanted to buy and resell the above units, since most sellers don't want to send out a piece without a firm commitment to buy. I had seen the Dodson and saw a listing by Pardales, who answered my questions and stated that this was an excellent unit. Duane (my dealer) doesn't sell Dodson, but had heard several of them in friends' system and they had always "sounded good". So, I pulled the trigger, and hit the jackpot with this unit. Pardales had said, "You won't be disappointed." No kidding. What a great seller he was. This sounds kind of obscure, but one tipoff was the obvious care he had taken in packaging the unit with a double box.
So, everything was evaluated via word of mouth or emails, second hand, but nevertheless it worked out extremely well for me. Yes, there are some who argue in various threads, and there are some disputes on this site, but my impression is that the Audiogon crowd is a (mostly) outstanding group of people with discerning (albeit variable) taste in high end audio and impeccable integrity. Pardales is a stellar example, in my experience.