I built a dedicated diode laser machine.
I also have a laser mount for the LR3, which I use for a “40W” (10W optical power) diode laser, but for the 5W laser, I built a smaller CoreXY maxhine for it specifically.
The smaller machine can move faster, which has advantages, and change directions faster. This makes handling outlines and complex shapes more consistent and even. Also, there is little need for Z axis control with a laser, so the machine can be much simpler. I also just wanted to play with my own design 
.
It would need tweaking for a larger heat sink but this is my thread for the CoreXY Laser Engraver