One has to approach the EVGA Hadron Air in three different ways. The first is the chassis design: It aims to give you the ability to build a fully fledged gaming power house in an incredibly compact chassis without having to sacrifice on power or an external drive bay. Bringing all these aspects to the table, including a 500W power supply and the slot-loading drive bay, it is quite alright to only have two hard-drive bays in a chassis of this size, though the optical drive bay is very restrictive, only really allowing for the use of one specific drive, which basically kills any hopes of having Blu-ray functionality for a reasonable price. The only available drive that fits is one from Silverstone, which costs nearly three times as much as other Slimline Blu-Ray drives. But the space for a GPU and quality power supply are unheard of in a case of this size.
The second is the power supply: Given it is 80 Plus Gold, with a potent, single 40A rail and sleeved cables, users can sleep easy knowing that their system is backed by an excellently specced unit. It would have been perfect had EVGA managed to tweak the balance of connectors by offering more SATA than Molex plugs, though.
And lastly, there is the price: While the US is getting a really good deal, it is less so in Europe. You are naturally paying for the whole package, including the high quality power supply in a tiny chassis, so one cannot simply compare pricing of the Hadron Air to a traditional PSU and ITX Case combo. Considering Sea Sonic's high-end SS-500L1U 500W unit costing 100 euros is very similar in spec to the included PSU, one could deduce that you are paying 100 euros for the chassis itself. While it may be a bit toward the high end of the spectrum, US readers will then benefit from a much better price/performance ratio at retailers like Newegg.
The Hadron Air ultimately works and does so extremely well; that is, if you are willing to shell out the price premium for the right to own such a tiny system while also investing some extra coin and time to source the right parts to make the most of it. EVGA just has to get the price in Europe to match that of the US somewhat because hitting the market with the Hadron Air at 169 or 179 euros would also free up the necessary budget for a slot-loading drive. Also expand the compatibility list of fitting slot-loading drives for more readily available units and the Hadron Air would get our Editor's Choice award. As it stands right now, it is an awesome chassis with incredible potential for tiny but powerful gaming systems that can really kick some serious behind; that is, as long as you are willing to put in the extra work while limiting yourself to specific parts.