We have a 6-30 on the combine, and as far as speed it depends on yield and what the shoe will handle. Usually in the 3.5 to 4 mph range. Corn yields range from 180 to 220 bu_acre. Just trying to get a little more capacity without much input. When we do decide to trade it most likely will be a '62, but we aren't ready to do this for a couple of years. The '52 is in good condition.