I have two questions for all you veteran PC posters/Prius owners. 1) Does the "Sound Shield" package (port option) affect the MPG? (extra weight) How? I understand that this is a "spray/fill in foam" type material along with a "tar" like undercoating/spray that they do. (correct me and/or add more info on this please) 2) Do you recommend it? Thanks guys, Aaron
