What year bike are you talking about?
It's an upgrade from stock.
IMO...it's a lot of $$$ and not a very good return on investment (sound at HWY speed), compared to some of the other options out there.
If maintaining a totally "pure" HD bike and parts are important to you, then it's your option.
I have a friend that is fanatical about nothing but HD on his bike and there is nothing wrong with that. To each their own.
IMO...explore the different options the reputable sled audio companies are offering, look at the common denominators (mainly RMS wattage per channel @ 4 ohms from the amps and the quality of speakers offered) and you will begin to get a feel for what you need to hear loud, clear music at HWY speeds.