RE: non floater low wing for 91 4 stroke
Of all the many planes I have flown I will say the WM Super Chipmunk is brilliant for your 90 sized 4C, its got flaps and retracts, flies really great. Also, the Pacific Aeromodels Edge 540 is another great choice. Both are well manufactured planes and both fly great! Much better than your 4* or Tiger II.