SFF = Small Form Factor, or a small case.
Have had both Aria and X-Qpack.
Neither are good for HTPC, so rule them out if HTPC is what you do.
(It is what I do, and have built and sold dozens over the past few years).
For HTPC, cheap, small, great cooling, plenty of room, and reliable, all come in Athenatech A100 series. Aria and Qpack are not in the same league, even though they cost twice as much.
Comparing the Aria to the Qpack.
Looks. Qpack easily wins.
Aria black front bezel has a very cheap, always dirty look to it because of card reader.
The Aria is one of those items that looks great in photo's, but not when you see it in person.
Finish on Qpack is modern polished aluminum look, and it always looks nice.
Too many windows on windowed versions of Qpack.
LED side vertical bars on Aria is way too much.
Both are too big for HTPC use.
Noise. Qpack wins. The Antec fan is louder (because 120mm fan is cranking, trying to cool the beast)
Cooling. No contest. Qpack wins.
Temps will NOT be any issue with Qpack. Great cooling layout.
Aria will have cooling issues unless you cut holes in case.
(note: You can use Zalman 7000 series with Aria, just as you can with Qpack. It fits).
Ease of use, setup and install.
Again, no contest. Qpack wins.
Qpack is a little larger, in all the right places.
Qpack has removable motherboard tray.
Qpack motherboard, etc, easy to install.
Aria motherboard, etc, PITA to install, as must remove PS and supports to work on it.
The Aria does have easily detachable side and top panels, which help greatly when installing components (or leave a panel off to help cooling).
And the big one everyone mentions.
Power Supply. Qpack wins.
Qpack use standard ATX power supply.
Aria uses proprietary power supply, so when it fails, you are screwed.
Antec Aria power supply is lowest quality part Antec makes, and they fail often.
Antec no longer cross ships, so when power supply fails, you can not use temporary replacement (because it won't fit), and instead will be without PC for about 3 weeks, which is about how long it takes for your defective Antec supply to get to Antec, which they then inspect fully before they decide to ship a replacement, then ground shipping for replacement to go from Antec to you.
(Most Qpack users are indeed using the stock power supply. New version even has split rails.)
For HTPC, Athenatech A100 (even the included 200+ watt FSP Group PSUs work great with everything).
For SFF game box, or just a cool looking desktop, Qpack.
For those that get excited when they hear Antec Power supply, and "think" quality, Aria.
Antec quality better?
http://forums.anandtech.com/messageview...atid=27&threadid=1676206&enterthread=y
http://forums.anandtech.com/messageview...atid=37&threadid=1753148&enterthread=y
http://forums.anandtech.com/messageview...hreadid=1592069&enterthread=y&arctab=y
http://forums.anandtech.com/messageview...hreadid=1361986&enterthread=y&arctab=y