Feasibility of three DC motor, optical encoder Servos running on Arduino ?

Will three DC motor, optical encoder servos work on an Arduino Uno or Leonardo? If not what is the limitation? Or is an Arduino Mega required?

Howard

After posting my question I lucked out and found the following web page.
http://www.pjrc.com/teensy/td_libs_Encoder.html

Notice the comment about best, good and low performance and the table showing the number of interrupts.

Howard.