Sigma wideangle for mirrorless

More and more manufacturers are making lenses for mirrorless cameras, that's a good thing for choice and competition.
Sigma has made a slightly odd choice with their second lens, a 19mm 2.8 (review). It's a 38mm equivalent on M4/3, so very boring focal length and only medium fast. But: it's small and light-weight, and apparently quite sharp, and it's dead-cheap at only around two hunnert bucks, so if one does not already have a lens in this area, it might not be such a bad choice.
And Mike Johnston has pointed out that 40mm is a good choice for standard lens, and I have to agree, it feels much better to me than the old standard 50mm length, which is sorta neither here nor there, it doesn't select out things, but doesn't take in a scene either.