I seem to be getting the best results sending RGB instead of YCbCr, but the perceived difference is very subtle so I'm not sure if I'm really seeing a difference. I'm hoping some of you pro calibrators know what's best for these TVs.
If the TV can do RGB natively, i.e. without conversion back to YCbCr first, I would want to send the TV native RGB to minimize any processing the TV has to do before displaying the signal. I have the Oppo BDP-103, which I assume does a first rate job of converting the YCbCr 4:2:0 off the disc into an RGB signal (probably better than the TV would).