The paper discusses two wide-scope soft-switching multi-level DC-DC Converters (MMDCs), and a comparative evaluation of these FB MMDCs is also presented. The discussed topologies have all merits belonging to conventional FB MMDCs, for example, smaller voltage stress on the primary switches, and no added primary clamping devices and modular primary structure. In addition, the primary switches of each converter can obtain zero voltage switch (ZVS) or zero current switch (ZCS) in a wide load range. The proposed FB MMDCs are assessed and evaluated based on their performance, components and topology structure indices, such as soft switching characteristics, current stress, power loss distribution, number of added devices and complexity of structure. Experimental results verify the feasibility and advantages of the new topologies.