First of all you can't tell what a system sounds like by listening to a vid, what it was recorded on probably came from WallMart! HKS real dual exhaust system sounds good all by itself. Most of the restriction in our systems is caused by the OE cats, you won't believe the difference! FI HFCs will make it louder but unlike ART pipes you'll be able to breathe with the windows down. ART pipes makes our exhaust major stinky
I suggest you attend a few meets and hear different exhaust systems in person, trust me that's the only way to find what you like!