RAID - which HDD is best for use in NAS? [on hold]

RAID - which HDD is best for use in NAS? [on hold]

I am about to set up a NAS server to organize some kind of cloud storage
system. So, I have already chosen Synology DS411 Slim to use as a server,
but I am not sure what to choose from hard drives:
Some people says that WD ans Seagate have very high fail percentage, but I
don't think that WD Red, developed especially for use in NAS serevers,
would have such a problem. I've heard that Hitachi is the most reliable,
but...
Anyway, it is better to ask sometimes then to buy new drives :)
What is the most suitable HDD for me, if I intend to use RAID5 with 4 x
1Tb HDD?