Hey Guys! Which External HDD should I pick ? Both USB 3, 2.5 inch , 5400 rpm vs 7200 rpm? Any big difference?

Basically one is the Western Digital My Essential Passport which is 5400 rpm and the other is Samsung 7200 Rpm, the HDD is going to be used mainly for data storage. Do you think the RPM's really matter in such case , would there be faster data transfer rate? Because I prefer the WD....but if there is going to be a difference I'm taking the samsung...