"Mercedes says Metris’ payload and cargo space will be 67 and 40 percent greater, respectively, than other mid-size commercial vans; reading between the lines, we figure they’re referencing the Dodge Grand Caravan-based Ram Cargo Van"
I don't know if that's a fair comparison considering the Dodge G.C. van was initially designed as a family hauler. If size is the determining factor Ford Transit, Ram Promaster and Nissan NV cargo have come to the party well equipped.