For starters the price of Corsair's AX650 is very high and puts it in a difficult position especially if we compare it with another strong mid-wattage competitor, the excellent Kingwin LZP-550 which recently received a major price cut and came down to $130. However the latter is available only in the US (in the rest of the world you will find it as SuperFlower Golden King 550W but with limited availability) and is backed by only a three year warranty. The Corsair AX650 enjoys a high availability, is backed by a seven year warranty and Corsair is widely known for their excellent RMA. In addition the performance of the AX650 definitely puts it in the high-end category since it features excellent ripple suppression, good voltage regulation and very high efficiency over the whole load range. Also the fanless operation at low loads/ambient, the fully modular design and the quiet fan at normal operation add more points.

Bottom line, if money is not an issue for you and you want to acquire one of the best mid-wattage PSUs on today's market, then the Corsair AX650 should be on top of your list.