Audio Systems: Ohms, cd mp3 player, 8 ohm speakers

Question
I recently purchased a 1994 BMW 325i Convertible.  I came with a tape player.  I want to replace it with a CD/MP3 player.  WHen I went to a local store they showed concern about installing a 6 Ohms stereo in an 8 Ohm system.  They said I could not install a CD player sold in America in this car.  Is this true?  Is there any concern about speaker compatibility?

Answer
Most cd players sold in america are designed to run 4 ohm speakers and are compatible with either 4 ohm, 6 ohm, or 8 ohm speakers.  you only have a problem if the spaekers in the car are lowwer than 4 ohms.  if you had 2 ohm speakers the cd player would overheat.  the only problem 8 ohm speakers would cause is they would not be as loud.  you can solve any of these problems by adding an amplifier.