Hi Andrew- You should read the data sheets. The motors are 5.8A and the PS is 14A. 3x5.8A is 17.4A. Since you wont run the motors at the same time and same duty you will not need 17.4A. 14/17.4=80% capacity. I think this will work. If it does not work it means that your motors will not be able to provide full torque. Depending on what you are doing this maybe good or not. There is no difference in a unregulated vs regulated at a simple level. Go for it and keep us posted on results. Peter