OM-D as a lightweight back-up camera. Recommended?

I shot with the 5dIII and the EM5.  I shot most often with the EM5 as most of the time, it fills the need with less size and weight.
For indoor shooting, the EM5 with it's 5 stop IS and a fast prime like the 25mm PanLeica - it's really a dream available light camera.  I've always been dismayed that IS does not exist for fast primes in the Canon line.  Typically canon puts IS on their F4 zooms for instance.
I use the 12, 25, and 45 most with my EM5.  The new 17mm Olympus lens being a 'tweener' and relatively fast may become my most used lens once it comes out.  For now the 25 stays on most often.
I'm not a big fan of the m4/3 zooms and am awaiting the day my SHG lenses focus properly.  But, then the system isn't light or small anymore.

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John Mason - Lafayette, IN
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