Hi just was surprised by the fact that you got a giant supersportster from great planes, I dont see it advertised on their site, I am building a 90 / 120 supersportster from Jim Fieldman / Don Amderson plans purchased from RCM plans as my 60 size has been destroyed by a faulty transmitter. As far as I new the 90 / 120 supersportster was discontinued. the weight of the supersportster is 10lbs and designed for fourstroke glow, if this is the same plane with a 72" span and area 950 sq" a weight of ten pounds the wing loading is great at 24.3 and a wing cube loading of only 9.4 with a gas engine which would add at least a couple of pounds still be OK at a wing loading of 29.1 but cube loading climing to 11.3 which is outside the favourable 9 - 10 for aerobatic and climing toward 12 - 13 for scale according to the web calculator I used http://www.ef-uk.net/data/wcl.htm. I have never seen them advertised for use with petrol, are we talking of the same plane if we are I think since I am in the process of building mine and at a stage where I could build for gas this would definately mean shortening the nose to keep CG and possibly make another set of wings for with slightly more wing area to reduce the wing cube loading. very interesting.