uncoated cutters should work even better on soft materials like alu/copper and even plastics and wood ,because they are sharper.But like you said : don't fix it if it ain't broke ,but if you do get that 100.000pcs. yesterday order it might be worth while trying.
Atleast sharper is better when it comes to copper and make sure the workpiece keeps as cool as possible.
i get some very nice results on uncoated 2/3/4mm four flutes on 13/16rpm's milling pockets at 2mm depths of cuts and just cranking handles.
And make sure to get the right coolant ,i used to hate how my cutting fluids would color my workpieces.
good luck.
Finally CHIPS you can have as much as you can without the doc. complainting about your cholesterol.