I purchased standard grade and acoustic grade indow inserts. I am sure they will help with insulation, but the acoustic grade make no difference with the street noise. I live in an old house and the windows practically fill the wall facing the street. My street is not even that noisy but you can hear everything, including three years olds playing in the daycare outside on the other side of the road. I would have just gotten the standard grade because the acoustic ones do not work. The salesman was just interested in the sale. He first claimed that most sound would be blocked out and after I reported that there was no difference in sound said that they really work best with brick homes. I hope they at least help with winter insulation because the acoustic grade windows DO NOT live up to the company’s claims.