Backup of my Synology

[Raggy]

I am starting to run out of space on my Synology DS 212. The two Samsung 2TB spinners are mirrored so I was thinking I could un-mirror them and buy a single 4 TB desktop drive as backup drive. Is this madness?

I have seen some keen prices on Seagate desktop drives but I can not see the difference between Seagate Backup PLUS and Seagate Expansion Desktop? I can find no details on what disk sits inside the cases, and the price is about £ 10 more for the Backup PLUS drive.

Or shall I choose a different maker of spinning rust?

 

[Raggy]

I have been thinking about getting 2 x 4/5 TB drives and expanding, but I am not entirely sure my Synology model support this. It is quite old after all.