I have seen the CHP Officers from the Riverside Office that are assigned to the Regional Gang Task Force use the all white slick top unit and only have the CHP star and Highway Patrol on the front doors. I guess everyone on the RGTF can get unmarked except for the CHP officers.
With that said I do not think CHP has many unmarked units. I have seen the MAIT Expedition was at least marked on the rear with only "MAIT".
I have to admit that I like the simple left/right, red/blue flash pattern. Nothing obnoxious, nothing that is seizure-inducing. And the whole front end going all-red steady burn in park mode... that's awesome too.