RX100 Jpeg + RAW
I'm not sure about the RAW part of your question, but I would like to mention that you can apply some of the art filters after you have taken the shot. So if you shoot Jpeg+RAW, you can simply apply the art filter that you want and as a result you will have 3 files: Jpeg, RAW and Art-Jpeg.
Anyway, RX100 will always save the original jpeg no matter what filters you apply.
Does that help?