Is Samsung G Series 2TB a good & reliable external HDD ?
You might also consider Blue Ray media for backup purposes (20+ GB per disk and the data is not destroyed if you drop it). Seagate and Western Digital would be safer brands than Samsung. The brands to really stay away from (in my experience) are Fujitsu and Hitachi. I have a stack of dead Fujitsu and Hitachi drives. I also have one dead Samsung. It is a good idea to back up important files to two or three different mediums, not just one external hard drive. Most of hard disk manufacturers have at least a few models that are not reliable, so research the model first.