I dont think like that.... rotary machines are gettin better but some tasks cannot be done so good like with coil machine.....

I agree about colour or line works, coil machines are great... but not for smooth realistic grey work, coil machine with perfect settings for delicate fast shading is much better that any rotary machine,
I agree that rotarys makin life easier, you dont need to fight with setting, but if real artist know how to tune perfectly shader machine he can create more precission and fine shading work.