I've been using Firestone for 5 years now, and I have to disagree with the other reviews. We have taken our Prius in twice in the last year to have the brakes checked, and both times that have said that there is plenty of life left in the brakes, and we didn't need to do anything. We get our cars regularly serviced here, and they have never suggested doing anything more.
Once, a dealer told me that my water pump needed replacing (they had my car for a mandatory safety check). I took the car to Firestone for a regular service, and they also pointed out that the water pump was leaking slightly and would need replacing at some point in the future. They said that it wasn't necessary now, but if I suddenly saw a large pool of water on the floor, then I should being it in straight away. That was over a year ago!
I have overheard them suggesting things to customers, but it always seemed clear to me which were suggestions that should be done soon, and which could wait. It's one of the reasons I keep going back!