I've never owned an inline but I don't see any reason not to use "real black" in one.

I've never noticed any difference in corrosiveness between "real black" and substitutes. If you have to think about that, you're doing something wrong. I simply clean my gun at the end of the day. There's no time for corrosion to occur and nothing to corrode with .. unless you're leaving your gun dirty.

Anyone who thinks there's two sides to everything hasn't met a M�bius strip.

Here be dragons ...