I installed the this NAS/HDD a few days ago and have started to use it with my Apple Mac.
Build quality is very good - the unit is solid, and it comes with a robust stand, power cable and network cable. Installing the software was simple - insert the CD and come back a few minutes later. The drive itself has a few LEDs on the front and is reasonably quiet. You can also restart/shutdown the drive from within the software, which is a nice touch!
I haven't had a chance to play around with it properly, but I did set up Apple Time Machine, which was stunningly simple - just install the drive/software and then start Time Machine - it was as simple as that!
What I do like is the ability to use as a remote HDD for iTunes (which automatically detected the drive), as well as have different folders to separate Time Machine backups from everyday files.
The software itself it quite intuitive, which makes up for the lack of a paper instruction manual. Saying that, there is a manual on the CD itself should you need assistance.