The 303 is open hole with a sterling head. The 80 is also has a sterling body and foot tube. The 90 is the same as the 80 but is closed hole. Better to go with a Yamaha, Emerson, Deford or even a Jupiter. Some Armstrongs are good and some just OK. The best part is that they are often VERY cheap to buy. I sold a really nice 90 about a year ago for $250.