The basic consideration is that all digital sources are YCbCr and the final format that goes to the DMDs is RGB. You have to decide if the YCbCr to RGB conversion is best done by the source component, the video processor, or the projector. This is an easy conversion with well defined conversion formulas, but that's no guarantee that it will be done right.
There are additional considerations with specific units. For example, the Pioneer HD1 BD player converts to RGB in the decoder\\processor IC. If you select YCbCr output, RGB is converted to YCbCr by the HDMI transmitter. You now have multiple conversions and that's a potential problem. It's better to select RGB output with this player, unless you are using a video processor that works in YCbCr, which also can add an unwanted conversion.
Another thing to consider is bit depth. YCbCr can offer more bit depth and whether it's needed or not depends on the type of processing before output.
I know that I did not answer your specific question. I don't know enough about your components to do that, but if I had to guess I would say use YCbCr 4:2:2.