Controlling multiple devices theory

I have an application theory I would like to get some input on. 

Take an application like a Servo Engine.vi, it controls communication with the servo and dequeues any servo commands from the main.vi to control the servo. 

Now my question is if you have multiple servos:

-  Is it best to only have 1 engine running and pass the Axis number through the queue?

-  Is it best to run the engines reentrant, so each one handles each servo?

I have done this both ways in the past I really don’t know which way is better. 

Thanks, Doug