The parting shot on mine about what is "wrong" with it could be that the preamps are bad (the PMD-620), or when you adjust the volume nob, it drops samples (ala the R-44). It could resample the digital input or not sync all of it's channels to an external clock (The R-4 among others). All sorts of shit could be "wrong" depending on what you want/expect the hardware to do, or a minimum accepted performance level. It could be a sterling recorder that is perfect in every way, but $1k for 8 channels makes me wonder...
I agree that there are quite a number of things we would like to have and that may not be implemented to our satisfaction with this unit (loss of signal during gain adjustments, not syncing the analog channels to the digital channels, etc). I guess we can only wait and see on that front. As to quality of the preamps, I expect that comparing/assuming something akin to the HD-P2 or DA-P1 would be the more likely reference point than the PMD-620. Not just since the latter is marantz not tascam, but since the tascam products are more in the pro/prosumer category and the 620 is more in the consumer category in my mind.
As to the quality vs price -- I'm still hopeful it doesn't mean bad quality just since the price is the same as for former 2ch and 4ch units. That's the way electronics go -- over time, the functionality or a given type of technology improves, but the cost stays the same (as opposed to the costs falling). Seems to be the way of the world with electronics whether its computers, audio/stereo receivers, tvs, dvd/blu-ray players, whatever. Why make the blu-ray player cheaper when you can throw in network connectivity and keep charging $200-250 for it? I'm hoping its this type of market activity at work, and not that they've made it 8ch, but made it all crappy.