There are a lot of places in Phoenix to wash your car, I'd suggest one of the other ones. While the prices aren't far off what other places charge. This place is consistently staffed by grouchy kids who seem incredibly annoyed you're at their place of business.
I realize the handful of times I've been to this location might not be scientific but I have more than a handful of friends on Yelp so it may indicate to you where the glowing reviews have come from.
You get what you pay for and if friendly service is something you're into then you're in the wrong place.