I know that is the right way to do it, however I don't live in the US. In here we only get lower end fosgates and alpines, and then all the boss & jensen cr*p...may be confusing but they are coming to a good point. comps sound differently on a person to person, car to car basis. what sounds "good" to one person may not be for you.
so try your best to go somewhere and listen to some of them. if you cant its kind of a crap shoot.... you see alot of guys on here that pay 500 bucks or better on comps and a week later they sell them because they just werent what they were looking for .