Ron,

As for "worth" the risk, time will tell, but a 3 bushel increase in yield at today's prices does pay with ground applied equipment.  If I were guaranteed a minimum of 3 bu. every year, I'd have to spray.  As for us, with all the weather we get out of the gulf, I think Asian Soybean Rust is a matter of time.  The good news is that it doesn't seem to be as aggressive in the States each year as it is in Brazil, but I think it is a matter of time before we have one of those years in Kentucky with our double crop beans.  Last year would have been one if we hadn't had that short dry spell in August.