Is the 2006 Prius quieter?

I picked up my Silver 06 HK from Redwood City earlier in the week. It's one sweet car. My sales guy told me that the 06's seem more solid and quieter to him. I believe I also saw posts a while back claiming the 06 model has more sound insulation, but I wasn't sure if it only applied to the Japanese model.

Any 04/05 owners out there care to meet up and test the sound levels? I own a rather nice digital sound meter. I'm in the San Mateo area. Contact me aridon99 at yahoo dot com