Ricoh GRD IV vs Olympus ZX-1

I would like to have a pocketable camera next to my DSRL, so i can have it with me all the time. I had a first series GRD, and i loved it. Unfortunately it's not in a good shape anymore. If it wouldn't cost 600, i would choose it, but i'm not sure that it worth double the money. Is it much better than the first version? How is the ZX-1 compares to it? If you have experience with them, please share your opinion. Thanks in advance.