I am skeptical of off-the-shelf external drives because the manufacturers generally do not use the best components to make up the drive. Low price is the driving (no pun intended) factor. Read some of the reviews and feedback before you decide on one.
I make my own using an external enclosure of my choice and a HDD of my choice.
I have an external WD drive as well and it is running fast, quiet and reliable for quite some time now. The only thing I don´t like about most of the WD external drives is missing "real" off switch.
But aside from that, WD would be my choice.
Also, you could do what Ubrales suggested and just get the drive of your choice and get an external HDD case.