I've got 2-1/4 duals with Flowtec Afterburners dumping just before the rear wheel. It's a nice, deep tone with absolutely zero "cackle" and it's relatively loud. A common reference point is the "drive thru" test. I don't have to kill my engine at the McDonalds drive-thru, but you can damn sure hear it when I pull up to the window.
I can also attest to Bumpster's exhaust setup. It's nice and mellow with a healthy tone. Maine won't allow glass packs, otherwise I'd have a nearly identical setup.