When I first saw in the paper and then at Spaceflight Today that Nasa was planning to send a manned mission to the moon using the SLS and Orion capsule, neither of which have had a manned mission before, I was aghast. It seems a mission like this is necessary to keep public interest based on the long intervals between launches and the SLS could possibly face cut backs or cancellations, something I've said from the beginning.
Nasas claims that it's under no political pressure, but to jump from a needed manned earth orbit mission to work out all the bugs in the system and go directly to a lunar mission is a recipe for disaster. With an earth orbit mission if something goes wrong the crew can quickly de-orbit to safety. If something goes wrong in the middle of an 8-9 day lunar mission the astronauts could end up dead. We could have the scenario we narrowly avoided with Apollo 13. Right now the scenario is for the free return orbit around the moon like Apollo 13.
Now this may seem like needless worrying but the second stage is a non-man rated rocket and the capsules life support systems have yet to be fully developed and tested. Nasa says that if the mechanics of the mission don't pan out then the mission will be scrubbed, but I still think that even proposing a mission like this is insane and the result of pressure on Nasa from somewhere.