I just did a quick comparison of the rf noise generated by our 2006 vs. the 2010 Prius, and posted photos. It appears that Toyota worked at improving low frequency noise (hf spectrum). I haven't yet tried moving my sensing antenna around to look for variations in rf levels at different parts of the vehicles. This was done with an antenna centered on the roof. I initially thought there was noise coming from the vehicle at around 100MHz, but that now appears to have been FM radio signals.