At the price Drobo is asking, the 5N is a versatile and well performing NAS with five drive bays. The hardware used is a good compromise when it comes to a reasonable combination of performance and price. Thanks to BeyondRAID and a software for PC and Mac, this is simply the most user-friendly NAS we've had for testing so far. Apart from that it has been combined with a mSATA slot, which allows for acceleration through SSD caching. Especially IOPS performance benefits largely from a caching SSD. Unfortunately we had to realize that our mSATA SSD, which we use for testing isn't compatible with the 5N. If you're interested in buying the 5N and a mSATA acceleration SSD, we highly recommend to check Drobo's compatibility
list. Since our drive wasn't compatible we will create another article at a later stage, comparing standard and accelerated performance.
If you're looking for an efficient and quick NAS, then the Drobo 5N is simply the NAS, which was the easiest to configure. The BeyondRAID feature is just great, but we still recommend using drives with similar capacities. Like with a conventional RAID array quite some space can be wasted if the capacity differences are large.
The Drobo 5N is listed on Geizhals for about 448 Euro.