[sdiy] FM vs PWM

[Mark Romberg]

what are the differences, in application, between FM and PWM of a VCO, 
ie, what are the musical applications of each and which is more 
useful/versatile? i only have one more space for a knob in my VCO, and 
so i have to choose.
i realize this is mostly a question of preference, but having not had 
the opportunity to play with either one, i dont know which i want.

have nice days.