Just so you know, not all multiple motor decks function the same way. Some, like the JVC uses one motor (I think it's reversible) for the FF and RW duties. The other motor is for the Capstan pinch roller & flywheel.
On the Aiwa TPR-950 (not sure about the other Aiwas), one motor is really just for cycling the servo soft touch controls to kickstart the mechanism.
The Grundig party center 2000 has what appears visually to be a 3-motor deck but I'm pretty sure that one of those motors is actually some kind of solenoid. Still, operationally it is very simple and high quality deck if it weren't for the material of a couple of gears that always break on them.
My point is that while each one of these decks have different characters of operation, don't judge the quality of a deck simply by the number of motors other than that yes, they usually are higher quality than 1-motor decks but will it result in higher quality sound recordings or reproduction, or was the extra motor used to provide a more luxurious soft touch feel of operation?
... just have to get myself M70 first! 
