Am I crazy? Considering OM-D over K-5II...

As you pointed out, these are two completely different cameras.  Here is why I will not buy a M4/3 camera:

1 - Sensor size.  Face it, bigger is better.  We would all shoot with large/medium format size sensors if we could put them in a DSLR like package.  We would all love to shoot with FF sensors in a K-5 or OM-D size body.  But since we cant you have to decide how small you are willing to go.  For me it is APS-C.  For me the gap between M43 and APS-C is too big and the gap between M43 and P&S too small.

2 - Format survivability.  I just dont think it can survive.  I see Panasonic and Olympus bodies being sold at fire sale prices and think "how are they making money?"  Off lenses?  Sigma is selling lenses "2 for $200" which cant be good for Oly.  And with Sony taking such a large share of Oly I wonder how long they will continue to produce the biggest competitor to the NEX.

3 - About those lenses.  Because of the 2x FOV crop you have to get a REALLY wide lens just to have a "normal."  The best selling M43 lens on Amazon is a Panasonic 45-200.  That means 90-400 effective.  Best selling prime is a 45mm Oly.  Again 90mm effective.  You are going to have to be pretty far from your subjects a lot of the time.  And none of those lenses scale up.  Let me say that again, none scale up.  I have a Tamron 17-50 f/2.8 for my Pentax that will work just fine on the mythical Pentax FF.  Even normal 4/3 lenses require an adapter to work on M43 but M43 wont work on anything else.  History has never been kind to dead end formats.

All this ties in together.  Lower sensor performance + limited lens lineup + real questions about format survivability.  If Oly stops making cameras will Panasonic keep the format up?  Doubt it.  Heck I dont know how much longer Panasonic is going to stay committed given they are losing money over all and photo is part of the problem.

The K5II and OMD are roughly equal in price.  But the Pentax gives you more choice in lenses, more choice in accessories and a scalable future.  M43 is limited across the board.  I would rather get an APS-C for times when I want best quality and a Q or a P&S for when I want as small as possible.  With M43 you are stuck making all the sacrifices and getting none of the benefits.

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Very happy K5 & K200 owner!
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