I have the WM cub 48... flying on an old OS 48FS... very scale like flying on this engine... I had trouble with the "wing tube"... After a few times flying with the two piece wing, my joiner bent... so I went to Walmart bought a wooden dowl the same size, cut it to length... and expoxied my wing halves together... It flies much much better... rolls, loops, snaps (be carefull), and flies inverted very well... Takeoffs are smooth, into a slight wind... mine is flying after about 30 feet... she lands very slow... I have flown the .40 and .60 GP Cub, and they are good models, but the WM is my favorite... It's very smooth in the air... and I used the tank and all the hardware included... I have had zero problems.