makar1: I don't know how much time you spend on tech stores... but just because USB 2.0 says 30 MB/s, if you actually run tests USB 2.0 rarely ever reaches those speeds.
As you've noted already, not all USB 3.0 are the same, and not all USB 2.0 are the same. You can pay an arm and a leg for the best USB 3.0 out there, or you can be smart and pay 0.50 cents per GB and get a nice 100 read USB 3.0.
