Just received a great little laser diode driver from DTR’s Laser Shop. (https://sites.google.com/site/dtrlpf/home/flexdrives/x-drive) It can be made to use PWM by removing one resistor and one capacitor, and adding the PWM wire. Available from 1.5A to 5A sizes. Should make using Laser diodes from Banggood etc,. a lot easier.