Gas millage specs....monte carlo?

I don't own one either, but I did have an 84 Caprice two door with a 305 and 700 R 4 tranny. I drove about 35% city and 65% highway when I had it. It averaged 20 MPG in Wisconsin winters and 22 MPG in the summer on 87 octane, 10% ethanol, gas. You should be able to get similar results with a conservative driving style. As far as flaws. Rust is always an issue and small block Chevy engines are prone to rear main seal leaks and timing chains lasted about 100,000 miles before they would stretch and cause problems. I've thought about getting one those cars too, but I'd get the LS version. I like the non SS front.