My experience: I had the dealer do it, which meant they had someone come out and replace it in thier parking lot on a rainy day. Didn't work well, it leaked and was noisy. Fortunately that one broke (I have windshield insurance). I then took it to windshield shop that sends out the mobile vans. They had the car 2 days where it was inside in a heated garage. There job was night and day from the dealer. Much better. No leaks, no noise no problems.