I'm not happy with my AD-7173A.
First one was Dead on Arrival (wouldn't recognize any media) so I RMA'd it. Tried it both internally and in an external enclosure and it was equally dead in both (the tray worked though).
The second one (replacement) is the one I have now, more about that below.
Third one was Dead on Arrival (wouldn't recognize any media) and bought from another shop, but that was enough attempts for me so I returned it and got my money back.
The one I decided to keep can only burn Taiyo Yuden 16x DVD+R media at 18x without creating coasters. All other 16x rated media I've tried, even some truly excellent MCC004, are coasters when burned at 18x. Burn quality is not so hot at 16x either.
The drive also makes re-linking spikes for many burns at 8x speed and faster which my BenQ DW1655 choke at. So I can only safely burn at 6x.
Scanning reliability is even worse than my NEC ND-4551A (which is almost trustable at 12x DVD scans now after being quite whacky for a while) with random PIE/PIF spikes at all scanning speeds.
The drive is an OK CD-R writer but not as good as my NEC ND-4551A.
Scanning reliability for CD media is also worse than my NEC 4551 with random C1/C2 spikes at all scanning speeds.
So I'm not a big fan.