Which manufacturer to choose is difficult, I guess.
I don't know any other brand than Synology, I have two of them, the DS213 and DS214.
Very happy with it, no problems whatsoever with streaming video (with NFS) to my 600X3D and streaming music to my Logitech Squeezebox Duet.
Since I have spent quite a lot of effort in photo's and home-made software, I use RAID on both NAS-es and yes, I had a diskfailure once which was tackled by the RAID setup without data-loss.
I replaced the faulty HDD and the NAS took over instantly and repaired things.
As far as I am concerned, I would recommend Synology to anyone, but that is my personal opinion ofcource
By the way, HDD prices are increasing nowadays, so don't wait too long with buying your NAS.
Ton