bojack: I think I knew a guy who had the Fried A3 with CJ tube gear, and it sounded impressive for a modest 2-way dynamic system.
As to your comparison of the DNA125 with the QS monos; was your DNA125 stock, or was it modded like the ones that Steve McCormack does? The modded version is definitely a step beyond the stock amplifier, and to an extent that I am cautious about the idea of switching to tubes. I suspect that the differences between the modded DNA125 and the QS amplifiers might be subtle.