O

I have two CNC routers in my shop - and haven't ever used a CNC
milling machine for wood - but would guess that 3000 RPM would be a
marginal spindle speed even with 4-fluted cutters. I'd suggest trying
it out before spending your money.

the only issue with rpms is cutting the edge grain. slower rpms can
peel off chunks of wood. but there are ways around that. other then
that you can go as slow as you want.
purpleheart machines great. I have not tried softwoods though. but I
can do it at 80 rpms as long as I am really careful on the edge grain.