The design of the QNAP range of NAS units hasn’t changed a great deal over the last few years, but now the company has come up with something startlingly different.The QNAP TS-453mini is something of an oddity. The obvious feature is, of course, the fact that this is vertical loading NAS unit, where the drives are slotted into the top of the TS-453 when the lid is removed in a kind of bread bin style.This design feature may seem a bizarre turn for QNAP, but it’s actually pretty smart. For one, there’s less of a footprint compared to front loading NAS units, with this box measuring 210 x 151 x 200mm. Secondly, it makes accessing the drives a little easier, and because of the way each drive is mounted, there’s significantly more airflow to help keep the internals cool.Lifting the magnetised lid off the TS-453mini reveals the four hot-swap drive bays and caddies. Each bay can take a 3.5″ or 2.5″ SATA 6Gbps hard disk or solid-state drive in a number of RAID levels. Beyond the drives is the motherboard, which has a quad-core Intel Celeron 2GHz processor (with a turbo boost up to 2.41GHz), either 2GB or 8GB of DDR3L memory (depending on the model, or whether you’ve upgraded it – accessible via a screw port at the bottom of the unit) and Intel HD graphics.The connectivity outside the unit is equally as impressive, with three USB 3.0 ports, two of which are located at the rear of the unit, a pair of USB 2.0 ports, two gigabit Ethernet ports and an HDMI port.The HDMI port means it can be used, as with other QNAP Turbo NAS units, as a dedicated media centre when hooked up to a TV or monitor. There’s even a remote control provided in the package. And when combined with the media centre apps and virtualisation software inherent to QNAP NAS units, the TS-453mini can be effectively used as a PC with a mouse and keyboard attached.This leads us to the operating system, QTS 4.1. QNAP has worked wonders with this OS over the last year or so. The sheer number of apps and add-on packages increases daily and covers just about every server function imaginable, as well as the aforementioned excellent Virtualisation Station and other drive management elements. Its only rival in the NAS world is the DSM operating system from Synology.The TS-453mini is a quiet, capable NAS unit. Having four drives bays is a great future proofing feature, as new drives can be added to a RAID setup easily through the management desktop. It’s also quite stylish, and you eventually come around to seeing the benefit of the toploading setup.QNAP looks like it may have trumped the competition with the TS-453mini. It’s a superb four-bay NAS unit, with a surprisingly good twist and plenty of extras to keep you interested for years to come. David HaywardA wonderful NAS with a clever design decision.