This site is actually really interesting. I haven't brought my car to a mechanic since I was 18 and I'm 32 now. I've had to fix just about everything and doing a quick spot check on some of the work I've personally done in the past the site looks pretty accurate.

For example over the years I've replaced several water pumps on vehicles that I have owned. Most of the time it's pretty straight forward but on my 88 Toyota pickup the water pump was burried and I had to remove the timing belt to get at it. Long story short it took a lot longer then the other water pumps I've replaced in the past.

When I plugged it into RepairPal, they accurately reflected the difference in labor and as a result the price quoted to change the water pump on the yota was about 2x as much as the one that I replaced on a chevy.