Sim is good, but IMO not a substitute for the real thing. Go with an LT-40 for your 1st plane, can't go wrong, they even look good on floats. then go for the J-3. The .70 engine choice will give you way plenty power even with floats. I have a .72 Saito on mine, with the GP 40 size floats (kit built) A ton of fun, looks and flies good on the water.