Yeah... I think carbide is going to be easier on the wallet.
Anyone try these yet? Micro 100 AL4 Tool Bit
"Super Carbide" ... or something like that.
I did get a price of $54 for a PCD (polycorbonate diamond) tipped AL4 bit from "J&M Diamond Tool". Probably cheaper from them if you buy more than one.
What grit diamond file do you use with your carbide bits?
About how many comm turns do you get before it needs sharpened?