Most hard drives obscure information like that, so the only real way to know is to test.
Gregory Smith's
PostgreSQL 9.0 High Performance has a lot of information for "benchmarking" hard drives, and the data in the book tends to mirror what the Arch wiki says.
But, does that mean the hard drive actually "starts" on the outer tracks (which would be faster) and "ends" in the slower center tracks? You aren't given that privileged information by the hard drive vendor.
Test.