Leprkon is correct. For the sake of reliability the drift of technology in audio has has been definitely tilted toward minimizing as much mechanical operation as possible. If you're in the service end of the business with a major audio manufacturer your see a field failure report every month for every model in your line. In general, the highest amount of returns are for the most mechanical of products, like a multi-disc changer for instance.
This is not to say that a multidisc changer will always break before something electronic within any given unit. Electronic parts, even those in production for a long time sometimes have "a bad run" of parts and rarely, very rarely these parts can get out to the field.
The problem with mechanical mechanisms is that, though they're often sourced from one or two big manufacturers and put in the products of other big manufacturers, all the testing in the world can't make up for Fluffy the cat's fur getting into the mechanism. Or if you repeatedly hit the drawer so hard to close it that you strip the (mostly) nylon or plastic gears.
Separates are the way to go. Especially if you're talkin' a DVD player which, at the bottom end of the spectrum, is fairly inexpensive anyway.
