Yes, the Pioneer has MP3, but Naks have good sound quality.
But Naks have reliability issues, but Pioneers need an additional box to
enable AUX in, while it is straight standard on the Nakamichi.
Also Pioneer is ISO, while the NAK would need wiring.

It is going into a Saab 900 convertable of 1992 vintage, so a classic
car shape, if not yet actually classic (the design was first used in the
1979 and only the bonnet shape changed until 1992/3), and will be
visible with the top down, so I don't want something that lights up like
an Xmas tree and has snowboarders or Mountainbikers or dolphins
slithering across the front.

Eventually will have a car PC fitted, so AUX in will be essential, don't
want a pre-amp only Headunit, but will be adding an AMP later. Must look
"Period".