I have the NU DW 163, and it's great.
Braxas - you might want to hold on to your warranty for at least a few weeks before flashing to a "B" - G7P9 runs the BenQ utilities, DL at 4X - so why bother with "B" and void the warranty? B7T9's thread shows many that don't like T9 any better than P9, "G" or "B". Considering the hassle you had with the refurb drive, I'd repeat my recommendation to flash up to G7P9 and hold there until the NU settles in.
Mine, at G7P9, is really doing wonderfully.