I'm in the same situation I recently installed ARH catless headers to go with my Xtreme and it's obnoxious. I'd love a set of corsa touring mufflers but not for 1,000 bucks.
From what I heard the Sai Li kit is straight forward. I had 5th Gear Automotive install it while they were doing some other work for me, so I don't have first had experience. I think it's good for around 900-1000.
Taylor is the man. He tuned my set up.
Red - Procharger D1SC, Sai Li Fuel System, id1050x, E85
Green - Procharger D1SC, Sai Li Fuel System, id1050x, E85, ARH Kittyless - Performance Tune
Pink - Procharger D1SC, Sai Li Fuel System, id1050x, E85, ARH Kittyless - Race Tune
I'm running catless but did it after passing emissions this year. Hopefully someone has an easy fix or I'll be moving to a non emissions county next year lol.