Analysis of information sources in references of the Wikipedia article "Mission Extension Vehicle" in English language version.
more than 40 different types of fueling systems... SIS will be carrying enough tools to open 75% of the fueling systems aboard satellites now in geostationary orbit... the SIS spacecraft is designed to operate for seven years in orbit but that it is likely to be able to operate far longer than that. Key to the business model is MDA's ability to launch replacement fuel canisters that would be grappled by SIS and used to refuel dozens of satellites over a period of years. These canisters would be much lighter than the SIS vehicle and thus much less expensive to launch.
ViviSat, a new 50-50 joint venture of U.S. Space and ATK, is marketing a satellite-refueling spacecraft that connects to a target spacecraft using the same probe-in-the-kick-motor approach as MDA, but does not transfer its fuel. Instead, the vehicle becomes a new fuel tank, using its own thrusters to supply attitude control for the target... [the ViviSat] concept is not as far along as MDA.
MEV‑1 has the ability to dock and undock several times during its 15 year design life, allowing it to service multiple customers. SpaceLogistics' initial service, using the MEV‑1, will extend the life of the Intelsat 901 satellite for five years.
more than 40 different types of fueling systems... SIS will be carrying enough tools to open 75% of the fueling systems aboard satellites now in geostationary orbit... the SIS spacecraft is designed to operate for seven years in orbit but that it is likely to be able to operate far longer than that. Key to the business model is MDA's ability to launch replacement fuel canisters that would be grappled by SIS and used to refuel dozens of satellites over a period of years. These canisters would be much lighter than the SIS vehicle and thus much less expensive to launch.