The pick of Mustangs in the 80-90 inch range are either 1. not real scale (as the topflite 1/5) or 2. excellent scale but Real Expensive (as in the Aerotech Model). IMHO a real good, real scale P-51 in that span would be worth designing. The problem with the smaller scales, say 46-60 is the weight penalty in adding the nice scale additions. These would include working inner gear doors, sliding canopy, full cockpit.. etc. For flying, the larger planes fly much better even with the additional weight. As for expense..if you look at the proliferation of Aerobatic 25% and Larger.. there is no scarity of those.. So I would say the larger planes are very affordable to many.. just my thoughts BobH.