Re: £490 will get you a WD 16TB raid 0 drive from Amazon. (2x8TB Reds)
anyone using Raid-0 for business critical data needs to be taken outside and shot, hung, drawn and quartered (IMHO) and then burnt at the stake if thay are still breathing.
As a minimum you need Raid-1 (Mirroring) not Raid-0 (Striping)
I've just had a 5-drive NAS spend 16 hours rebuilding itself after one 4TB HDD (WD) went Phut.
Thankfully it was configured as a Raid-6 array.