I've pretty much settled on 9-10 mph as the optimum speed for the row crop rig, all things considered.  I have ran it as fast as 15 but I believe over the course of a season I can get more done by keeping moving at the slower speed, in our conditions.   The floater will run at 19mph all day long and get along fine, but the boom is not trying to stay as close to the ground and the wide tires make a big difference in the rock and roll.  

I think we are probably not terribly far away from 20" so far this year here.....and we are still a little behind normal....and there is no way to predict whether it will be a drought or not here until about the end of August.  If it rains two or three times in July and August, it's not a drought, if it doesn't, it's a drought.  Nothing that falls now matters.