DVD reading speed is x1, regardless of the "x-##" number on the drive. The "x16" speed advertised (on say the Pioneer 106S drive) is essentially meaningless, apart from giving you a general idea of the speed of the drive at reading data. The drive currently thought of as the "fastest" DVD drive for reading data, DAE, etc. is generally thought to be the Lite-On x16, which reads data at about x48 rate.
Fortunately, it's also a high-quality drive, quiet, extremely cheap, and
sold on Newegg.com 