The QBD76 doesn't get blown away by the Dave, it just gets slightly humbled by it. The Dave does everything a bit better, one can still hear the same information but it's fleshed out, textured, located a bit better.
Indeed, it's been mentioned in this thread, if not straight up stated to be a fact, that our ears are so used to hearing music played back in a mechanical manner that we have been acclimated to an artificial sound which has become the norm. If we hold this statement to be true, then any upgrade, even if we were at 500,000 taps at the moment, might not register as immediately apparent to the ears as it would to the brain. Well, I mean, I have no idea what 500,000 taps would sound like actually, but I can only theorize. It might be a huge jump between 166k.
Actually I just used your post as a catalyst for my thoughts, and not necessarily addressing you specifically. Because...
I had this dream. No joke, I actually dreamt this, that I went to the Chord factory, and I was hanging out with John Franks and Rob, along with some smoking hot employee of theirs, and for some reason (although this wouldn't happen in real life), Rob let me listen to a "DAVE" that was already at a little over 1million taps, but he explained that he couldn't put it out yet because they need to make money on the 500k, 750k tap models, first, otherwise they would kill their own market. I knew this made business sense - even if it was screwed up - but man, it left me feeling pretty hollow. Rob said, "I mean, why wouldn't I have already reached 1million taps, when all it is is a matter of programing." I was shocked!
Anyway, of course it wasn't real life. I actually woke up not thinking about Chord, but more like, "What if they already have the cure of cancer, but they'd never let us know because there goes all the big money for doctors, pharmaceuticals, hospitals and the like."
Why am I writing all of this? Well, I guess I just have the DAVE on my mind. It really is a brilliant piece of gear.