It depends. Sony does not make drives by themselves, they buy them from different manufacturers like Liteon, Benq, Samsung or Nec and put their label on it.
There had been a collaboration between Sony and Liteon (including development) until recently. The Liteon drives built together with Sony can be identified by the first letter of the drive name. It is a "S" like in SHM-165P6S or SOHR-5239V. With these drives, there is no difference in hardware, and if you know the names of both, the Sony and the Liteon, then it is often possible to change a Liteon into a Sony and vice versa.
Liteon has now teamed up with Benq (and Philips).
Sony and Nec have joined to Optiarc.