Hi Ernie , Thank you for the link to the photos of your plane . I can see where there would be no spacers required since those SFGs don't extend beyond the wing to the aileron as mine do . You see , if it weren't for the spacers on the Funtana the ailerons would bind on the SFGs . I would like to hear of your experience with flying it both with and without to see what you think of them when you get to flying it . I will say that although they didn't seem to improve what I call "prop hanging" (hovering the plane in a vertical stationary position) much , they most certainly did improve the Knife Edge maneuver quite well . What I did was a couple of flights with , then a couple without , back and forth , I installed and removed them around 6 or 7 times and by far it was the Knife edge that was most improved . I never noticed any reduction in speed or need for additional throttle to maintain approx. the same speeds with or without them but then again they have no tow in like yours do . Scale also makes a good point in that these twisty acrobatic types really aren't about top speeds , and so a bit of drag in exchange for maybe a slightly greater stability may be an acceptable trade off .

PS , Sorry for the crappy cell phone photos , but I figured I'd throw a couple of shots of the Funtana's SFGs in just for grins