@mdrone Great News that you have been able to receive a demo' of a DAC. Carrying out the footwork and experiencing the sonic being created with ones own ears and evaluating the sonic as a result of perceptions being created is a extremely Valuable use of ones time, in relation to learning about audio set ups.
Out of interest the model demo'd being the Synthesis Audio Roma 69 DAC, does not seem to have appeared anywhere in this Thread. How did you discover this model? I see it is with a proportion of the circuit being a design as a Tube Circuit.
Did this get demo'd in a Dealership Premises or the Home System?
I own a Valve DAC with E88CC Tubes and have experiences of it compared to SS DAC's.
I feel very confident in stating this DAC does not create a perception of being overbearing, it has airiness and a voluminous room filling presence, that is always commented on for the attraction it creates.
The sonic trait being described by yourself, after extending listening could become a detractor, as like a overwhelming Bass Bloom, and become a repellent, where listening experiences develop into something to be endured.
Caveat Emptor is always ones friend, try not to pull the Trigger on a purchase prematurely.