Is it a good idea to buy CD players over 10 years old even it is a reliable brand?

I'm not sure I even belong on this blog. I bought a used NAD CD player, built in 1999, for the princely sum of $50. The display is shot, even after replacing the backlight. But it still spins discs and has a digital output that I utilize through a fairly recent Arcam DAC. The playback, trough it's resident DAC via the analog out, is also listenable. I assume this deck will crap out, at some point, never to be repaired but replaced with a similar machine at a similar price. 

I would not buy a 10 year old player, even if its moving parts are still available as of today you have no guarantee that they will still be available a couple of years from now. 

From how the question is phrased, I'm sure that Faust understands that disc spinners can break down, so I'm definitely in the camp of being reluctant to buy these -- for one thing, you just simply don't know how many hours are on it. I had a wonderful Proceed PDT3 that just conked out a year ago after 18 years of use and I had used it heavily! And it was the transport mechanism and could not be serviced. So as others opined, for more expensive disc spinners make SURE that they can be serviced.  
  I replaced my transport with a media server.

Comment #2: I don't think you can assume that players today are better than those of 20 years ago at a roughly similar price point. Companies like Madrigal, Mark Levinson, were driven to produce fantastic players in the new field. Today? I'm not sure they are and I've heard mass market players, such as a Marantz I recently auditioned ($400), that had all that digital hash jitter that we thought should have vanished by now....

It sort of boils down to pride of ownership. A used Esoteric is a nice piece of gear that looks and feels like a fine instrument. You will appreciate the quality every time you use it. I tend to do the same thing as you're planning - I buy nice high quality used gear that I can afford. In fact I don't think I have anything in my system that is less than 10 years old. A couple years ago I went to AXPONA and concluded that my system can compete with almost anything except the super high end setups. I'm not sure we have actually come that far in sound quality between the top end gear of 20 years ago and today.