I have the TRD Duals which I installed myself.
http://www.tundrasolutions.com/forum...h-sound-clips/
http://www.tundrasolutions.com/forum...exhaust-sound/
You should be able to find mounds of info in those 2 threads.
Ask me if I'd do it again, yes, in an instant, but ultimately it's your choice if you want to spend the money.