Vulcan, New Glenn, and the Falcon Heavy really aren't in the same league as the SLS, at least as far as lifting capacity is concerned. I think the SLS is an ex

Vulcan, New Glenn, and the Falcon Heavy really aren't in the same league as the SLS, at least as far as lifting capacity is concerned. I think the SLS is an excellent use of NASA's time and money at the moment. They're using proven technology to build a system that they can either: - fall back on in the event that commercial companies aren't able to deliver something comparable - still act as a viable launch platform if cheaper alternatives are somehow disabled (e.g. another Falcon failure)