TweakTown posted a review on the QNAP TS-509 Pro Turbo 5-Drive NAS Server
Today we are moving the spot light to NAS Servers with the QNAP TS-509 Pro. The 509 isn’t designed to sit in an enthusiast’s computer room, but many will eventually end up being used by power users like myself. If the Thecus N4100PRO impressed you with features, prepare to be blown away. The TS-509 Pro goes far beyond anything a normal consumer or prosumer would ever use under normal circumstances. The good thing is that QNAP has mastered ease of use when it comes to configuration. Many features that you may have passed off as unusable for your situation will eventually get used because they are just so easy in implement.QNAP TS-509 Pro Turbo 5-Drive NAS Server Review
As you can imagine, feature rich comes at a cost. After digging through the web I was able to find the QNAP TS-509 Pro Turbo NAS listed at MWAVE for 899 USD. For comparison Thecus makes a similar 5-drive NAS, the N5200PRO. The N5200PRO is a step above the N4100PRO and has a few more features, but not as many as the QNAP TS-509, with a 664 USD price to reflect that.