As the successor model is already there, the price has become so incredibly cheap, unassembled get a server with ECC RAM in such a sleek casing probably not even for twice the money.
From the machine can be much more than make HP admits: it fit in 16GB memory, a BIOS mod Server is hot-swappable and can connect up to six hard drives.
I go here the FreeBSD based NAS4Free with ZFS as a filesystem and am very happy, especially because you can outsource more services (database, CMS system) in jails.
The thread with all information from Hardwareluxx has also been called (Search times for "HP ProLiant MicroServer Hardwareluxx", then you can find it), there really are all information.
However, I would however recommend the version without 250GB drive with DVD and 4GB RAM, because boats can fine from a USB stick (this extra-slot on the motherboard) and a DVD drive, you can start more in doubt than with the 250 plate (as a data plate is today barely sufficient and for a sufficient system's USB flash drive also no SATA port occupied). Also can be a 4GB bolt easier to 8GB upgrade (or sell) as a 2GB bar.