They do have exceptional customer service, there have been times I've paid more to order something from them just because I trust their service so much.
It really shows how good a company is that people will pay more to order from them primarily based on the after sales support.
I have bought things from a car stereo website (Crutchfield) more than once, they are in no way the cheapest, but the customer service (and the fact I get free next day delivery) and 99% of the time they will include accessories free more than make up for it.