While I haven't used it on my own maps (I'm still very new to this), I *have* rendered one large one I scanned in... and it works pretty well.
That is an amazing program. I know that some of the other folk around here have been able to accomplish such things, but this was too easy. I've thrown in a couple of my world maps with itty-bitty fonts on them, and this allows it to be entirely readable.
Thanks for the find!