It's hard to find any definite info on the sub handling. So much conflicting info out there, even NAD support is confused about it. Denon support is terrible too unfortunately.
The good news is that I don't think it matters much in practice. Yes, if you measure it with the right tools you can probably tell, but this past weekend I played with my NHT setup and a cheap amp that has no bass management, full signal to both speakers and sub and I tried different crossovers on the sub, my ears couldn't really tell the difference.
It may make a difference if the speakers can play down to say 60Hz. Mine only go down to 85Hz and setting a crossover on the sub at around 100Hz or even higher seems to be fine. Now there could be a problem if the amp decides to only send to the sub < 80Hz, you may end up with a gap between 80Hz and what your speakers can handle.
It's unfortunate that we don't get clear info and the only way to know for sure is to try the amps, which gets expensive rather quickly.
The NAD D 7050 is way out of budget, but from what I read it's actually comparable to the Denon PMA-50 in terms of chips used, in fact Denon uses newer revisions of the chips. But looking through the Denon manual there's no sign of any bass management at all.
So far I'm trending towards the NAD because it's smaller, cheaper and I don't really need the extra formats the Denon supports. What I don't like about the NAD is that it doesn't look as good horizontally as that's how I'm going to use it. I sound picky but for the money, I think they could have gone with a design that works equally well both ways and the display flips based on position like it does on the Denon.