Has anyone had the dealer install the satellite kit? Is it that much better than the FM modulator?

I just got my TCH and had Sirius in my old car. I took the antenna and receiver out of the old car and installed it in the TCH. (Being very, very careful about the paint on the TCH). It works fine, however, I noticed that due to the powerful antenna on the TCH I had trouble finding a clear radio station. I also noticed that I need to turn up the volume when I'm on satellite, compared to normal radio stations.

My dealer will charge me $400 to install the adapter for Sirius on my TCH and I was wondering if anyone thought it was worth it.

PS - I LOVE the gas mileage