When people talk about B/W quality, I haven't interpreted it as referring to them being more reliable (whichever manufacturer is mentioned, we're dealing with 15+ years old machines that were intended to go a few years, after all), but instead having a more solid "feel."

That's a subjective thing by nature. Could be the flipper patents, the parts differences, build process differences, or nothing at all. I definitely feel a difference and prefer it, and have had non-pinheads remark on it to me, but it wouldn't stop me from pursuing other pins. Pros and cons, etc. If a person doesn't notice a difference and can thus get the same experience and more bang for the buck from DE, cool.