here's my testimonial. i sent my wira aeroback for chassis foaming last week. service was fast and efficient. completed less than 2 hours. immediately the noise level inside the car on the road dropped but in terms of handling no difference. only after 3 days i can feel the ride improves and it gets better and better until today. for sure i'll return soon for more soundproofing - i'm thinking fender, and more foaming - door sill and A frame. highly recommended!