The whole idea is for them (imho)is to replace the 8's.These airplanes can carry over 20 ton's in the belly's (1/2 of a DC8 load) and the rest will go on 88'X125' pallets, not containers (cut up in 3).In any case, they will out perform the -55's, more payload and longer range.I personally don't see the problem.I do agree you can utilize the airplane better with a cargo door.But to out run the 55 series, you don't need it.