I recently replaced my GX100 with a GX200 to get the large RAW buffer. Most of the differences between the two cameras have been described in the various reviews and postings I've seen. For my purposes the faster handling is a huge improvement and I'm willing to put up with the noisier images at ISO 1600.

There are two very minor differences that I have not seen discussed in the reviews:

First, the DNG files from the GX200 open with too many pixels in some applications; the extra pixels show as a vertical black stripe on the right side of the image. From what I've been able to determine from other forums, this effect is present in some applications, but not in others. It depends on how the application implements the handling of DNGs. In my case, since I use a Mac, and since most applications on the Mac (Preview, Graphic Converter, iPhoto, Aperture) actually use the same bit of OS X to open DNGs, all these applications show the black stripe. I understand other, non-Apple applications, do too. Adobe DNG converter does not show the stripe on my system.

This is a change from the GX100. Its DNGs open correctly, the same size as the jpegs, with all these Mac applications. So Ricoh obviously changed something about the way in which it writes DNG files between the two cameras. Whether Ricoh is no longer strictly standards compliant, or whether many of the RAW applications out there are out of compliance I don't know.

The result of all this is that every GX200 DNG I take must be cropped. This isn't hard in Aperture; one can use a batch lift/stamp. And, in my case, essentially all my photos need cropped anyway (Ricoh has not yet implemented the much desired "automatically remove telegraph pole from subject's head" button). But it would be nice if Ricoh changed the firmware to behave as the GX100 did.

This problem only affects DNGs; JPGs have exactly the correct number of pixels and no black stripes.

The second change in the GX200, compared to the GX100, is for me an improvement. Many of my pictures are taken while hiking or bicycling and my sunglasses are polarized. The GX100 must have a horizontal polarization filter on the screen because the LCD screen is perfectly useable viewed through polarized lsunglasses when held in the landscape position but when turned 90 degrees to portrait orientation the screen goes black as the polarization filters cancel out.

On the GX200, however, Ricoh seems to have eliminated the polarizing filter on the LCD; the screen is viewable from all angles through my sunglasses. This is good.