RE: wing tips!
Umm, regarding the Funtana 40...
It tip stalls during low speed pull-ups, to the right always, I might add. I feel that the wing rock is caused by the same mechanism that causes this tip stall. The manner it stalls sure looks grossly analogous to me[X(]. And I have tried a whole range of CG on my Funtana 40, from 5.75" to 6.25". Wing rocks @ harrier no matter where the CG is at on mine.
Therefore, I will try the tip plate. If it eliminates the tip stall as well as wing rock @ harrier, then perhaps we will find the true cause of this wing rock.