Another thing that is very appreciated is the ability to quickly swap the modules. You can add an adapter plate that attaches to the max 4 module holder on the back, but which has a dovetail on the front. The dovetail perfectly holds the IR module, while the back still fits older machines. And the future machines could have only the dovetail holder as default. Or any other holding system with quick change and backward compatibility (older models).
Oooh I like that idea!
Would it be possible to use that module on a NEJE 5?
The IR Module is a nice addition to have -
a further nice addition would be an up to date fully enclosed laser system with an internal filtering and fume/smoke extraction. When working on metal/plastic projects we will be subject unhealthy fumes even more so than on projects working on wood.
It would be even cooler if the enclosed system would have a closable slot for the occasional bigger sheet/material and a pull out tray for offcuts or tiny party that fall through the honey comb.
For pricing - 300€ would be really good.
This is really exiting news.
I have used the old Neje 3 max for a long time and have now just ordered the Neje 4 max v2. Im building a extended laser setup for it. The goal is to be able to engrave up to 700x2000mm wide objects. I mostly do leather work, but can see this as a good way to expand into full guitar engraving, signs etc.
A “metal”-module would be super interesting for more music related work like effect-box-engraving, neck plates, control plates, custom amp control plates, back plates, large metal signs, custom knife etching, jewlery etc.. It opens up alot of possibilitys. I have still not tried any of these with my new E80 module, so I don’t yet know what is possible with it. 
Price point, about the same as other low watt ir-lasers. ~300 euros would be nice.