Hi all, thinking of buying a pair of Rinehart 500-0500 slip-ons for my Roadmaster. I'm not looking to do Stage One, not looking to remove cat and not looking for more power. I just want a nicer rumble than stock. Who has them, was it worth the $650 US in your opinion? My dealer said if I put them on he'll flash my ecm if I want. 2017 Roadmaster.