Peter, so far the 12" and the 24", the 4" in a couple spots on the corners. I don't see anywhere near the lines with these full radius anvils as I did with the flats I had in the other machine. Very pleased thus far. The cast machine is showing the 16 gauge who's boss!
For reference, here's some of the lines we were getting at last years class using the anvils with flats on a fabricated steel machine...