The EOS 6D has a full-frame sensor that gives you the typical full-frame look at almost half the price of the 5D mark III. That sounds like a bargain. But for HDSLR the beta model of this camera shows that it's not quite up to the standard we'd like to see nowadays.
It's the aliasing and moiré patterns that have haunted HDSLR cameras since they came out. A very unpleasant side effect that we would like to see gone from our video recordings. Though soft the 5D mark III delivered a very clean image finally free of aliasing problems, but it looks like these have come back to the 6D again.