Although there are negative comments about the EM-5's 12-50mm kit lens with regards to its f6.3 aperture, my take is that it should complement the EM-5 well as the camera can handle higher ISO., i.e, the lens is designed for the camera's capabilities.
As the EM-5 is weather and dust sealed, this splash and dust proof lens will be good together when used at the beach, swimming pool or boating.
If the body is WR then then lens should also be WR when the situation requires it.
So yes, I will get the body together with this lens as none of the lenses I have now is weather resistant.