|I love a light kit...so although I just went full frame (D600), I am still on the fence whether that's the kit I want to carry hiking into the Grand Canyon in the spring.
I've considered going to Micro Four Thirds even...thinking how cool it would be to have a 100-300mm lens, on a 2x crop factor sensor like the OM-D or GH2, so light and giving me a 600mm effective focal length! But I've also come to appreciate the benefits of higher resolution--heck, I love the 20mp I get out of my little RX100 (very sharp, lots of detail) and that swayed me to go to FF and the 24mp D600.
Yet I still crave lightweight and compact. I could go for a M43 camera...but I'd have to buy the camera and lots of new lenses, I'd lose some resolution and of course it's a smaller sensor too.
Which finally brings me to my point...now there's the Nikon 3200 and 5200. 24 MP on APS-C, I can use my fairly light lens kit, or my 70-300, and get 450mm effective focal length. Like M43, these also have the benefit of the articulating screen, something I think would be really good for landscapes (where I often shoot from a low perspective).
My feeling is that I can get almost the same results as the 2x magnification in M43 just by cropping a APS-C 24mp sensor (since the m43 cameras are 16mp and below. Right? If I cropped to 16mp, what's my effective magnification? Feeling a bit "slow" now,..I am not sure how to calculate it...that's 2/3 size, does that give me another 1.5x magnification...for a total of 2.25x?