Well depends what you want really... If you just want it put in your car to play music, I dont think it matters where you go (too much... there are some places that would fist you)
Anyway have you bought the gear already? If not I would probably recomend going to have a talk to them first. From my experience I found they go in to more detail, explain to you what does what, why you do one thing over another, why for what your doing one product is better than another etc.
Not knowing the research you have done, a properly good system is not only has a clear sound, but its staged properly etc. If all you want to do is just listen to music, and really dont care about how its been put together, you probably dont need to go to that extent.
But to answer the question, yes they are good. It is the ONLY place I will ever buy car sound gear again.