Open Camera does support RAW capture. However, it seems to only use the wide-angle lens. It doesn't capture the image at the same zoom as the co-produced JPG image.
Also, it doesn't seem to handle low-light situations well.
As long as you have favorable lighting conditions, it seems to do pretty good. If you want a non-stock camera (that isn't a GCam port) and works without having to make XML file tweaks (*cough* GCam), then Open Camera is not a bad choice. As the standard cliche caveat goes, "Results may vary."
I still prefer the Samsung stock camera and Expert RAW cameras though.