I mentioned it before but I really like the GX200 JPGs at ISO up to 200. They are very good and I have no problems with using them. Especially the b&w JPGs finally look more like the GRD I. No idea what went wrong with the GRD II but for a flagship camera to have such excessive noise reduction in JPGs that can't be turned off is not good. The GX200 and even R10 are a good step in the right direction even if they are still not where the GRD I was.
The handling of the GX200 is great but not as refined as the GRDs, you can also not quite use it with one hand as well and the GRDs just 'feel' better.
One thing though if you consider the GX100 or GX200, get the LC1 lenscap. This is the best accessory Ricoh produced and will make your life much easier, the lenscap is a pain. It is a simple but great design and if you search about it you will see adaptations for the Sigma DP1 and the Panasonic LX3.