John,
I believe that you will find that the bellows extension are somewhat limited on both of the unmodified F&S and Korona cameras. I have encountered one fellow (I believe his name is John Hoyt). He has a site covering a F&S that he restored. As I recall, he had a 450 Nikkor M lens on that camera. So it would have at least 18 inches of bellows draw and probably several inches more. Unfortunately, that seems to be the nature of things and one is either relegated to buying something like a new Wisner or Lotus or dealing with the older banquet cameras.

The shorter lenses that cover the format are the 355 G claron and the 450 M Nikkor. Sandy King has indicated that the 14, 16, and 19 inch Dagors may cover but should be checked before purchasing.

My Korona had been modified by a previous owner (installed a supplemental extension rail beneath the original rail). New bellows were then fabricated by Western Bellows and I have 36 inches of bellows extension now.

The present owner of your camera should be able to give you the bellows extension of the camera that you are considering.

The F&S seems to have front tilt, geared rear tilt, and swing. Would appear by design to be more stable then the design of the Korona. However my Korona is solid with the mods that were done. I can tell you that there is no comparison in viewing a 12X20 groundglass and an 8X10 groundglass. My 4X5 seems almost toylike now. Hope that this helps, sounds like fun.