we're installing my Gfs H-pipe tonight (h pipes are slightly less raspy than X) and have 4 resonators on the car lol ... hopefully it helps.
we have 2 "brand X" resonators we got in the over axle pipes from my buddy, I have no idea what they are, my 2 stock GT mufflers welded into the H-pipe itself, and then pype bombs out back ... hopefully we get a clean / aggressive tone on the stock headers. I'll do my best to grab a video.
I know a lot of people just go with 1 large 18" or so resonator, but the V6 exhaust is basically just 1 long straight section, and I wanted to break that up as much as I could, because that in part contributes to the rasp. The rest is just the nature of the beast, its a 60* fast revving, v6 ... it will have rasp.