@kytta I'd go with SSDs for external disks if they are supposed to be taken on the go.
I recently got myself a Crucial X6 with 2TB to move around data between my devices and take it with me.
If the drives are supposed to serve as external back up drives only and will mostly be stationary, then go for cheaper HDDs.
As far as brands go, my most reliable external hard drive is a Toshiba, which I had for years.