I have said this numerous times wrt to the engraving – not cutting – I’ve done on wood, chipboard, ceramic tile, and glass. I believe my 2.3W Banggood/Eleksmaker laser modules do a better job than most of my higher-powered lasers because they focus to a much nicer spot… and I suspect the smaller die/geometry and/or a better lens is probably the reason.
That said, I also have the Neje A40640 dual-diode laser module that I’ve used to engrave and cut a fair amount of 3mm plywood. It is the only higher-powered laser I own that I think “competes” with my 2.3W lasers for engraving purposes because of the “square” spot geometry it features… and it, of course, cuts far, far better.
I’ve used various GRBL-based (Grbl 1.1f and 1.1h) controller boards and use GRBL almost exclusively now because I believe it to be better and safer for most laser operations (about all I do nowadays) than Marlin… primarily for its M4 dynamic power adjust and near-instantaneous pause/resume. The recent Laser danger! discussion also seems to bear that out.
– David