WTB: used External HDD 500GB WD or seagate USB powered

I want to buy Used External HDD 500GB WD or Seagate USB powered without any bad sectors.

Go for Seagate only if its new. I wouldn't recommend used HDD's. They never perform up to the par.

Thanks for your suggestion. Appreciate

I think WD External with USB 2.0 is a good offer as it does not require external power source. Suits best if you have USB 3.0 onboard. Else go for Seagate or WB External with power cords.