Well I flew the UCD for the first time today after having removed the top 2.25" of the rudder (see earlier posts and pictures). It flew as hoped for with very little coupling needed. The plane was as stable as it has always been in normal flight. There is no apparent loss of rudder control (remember, its a huge rudder to begin with) and the plane still does knife edges and knife edge loops with ease but now without the need for a lot of mixing. Transitioning from a left to right or right to left knife edge can now be done without a lot of roll or elevator correction. It's now flyable on hard rudder maneuvers with just manual use of the sticks. However, after several flights I did reset 3% elevator mix (used to be 12%) and no mix for ailerons (used to be 5% mix). Flat rudder only circles are very easy now both upright and inverted. There is less wing rock in harriers and hovering even seems a bit easier. I wish I had done this from the beginning but who knew? I agree with NOSRAM's earlier post stating "for all its good points its a shame that Great Planes couldn't have finished the job, with no rudder cross coupling, and a tank at the correct height."