More than a year ago I had purchased the Max 3, before the Max 4 was released. I really found the z-axis interesting, so when Neje reached out and offered a discount to upgrade, I was happy for the opportunity.
First, I'm really glad to see them selling direct on Amazon. That makes the purchase a whole lot more convenient (at least for me), though purchasing directly from that wasn't difficult, the shipping just took a little longer / I had to make sure it was in stock in my local region.
We made a bunch of wooden covered notebooks for Christmas presents this year, and I was happy I could use the E80 module instead of the A40640 that came with the Max 3. I was able to do the cutting and engraving in half the time. As you can see from the stack, that time added up.
I picked a diode laser over a CO2 for a few reasons. Cost was certainly one of them; however, I also liked the simpler setup (no chiller needed) and flexibility (totally possible to engrave larger items by moving the laser to the item).
I'd quickly recommend this laser (as well as Neje in general) to anyone looking to start laser engraving / cutting. The setup is easy and straight forward, I've had no issues working with LightBurn, and - as evidenced by the Max 4 - they continue to improve on their design.