If it's a show car, what difference does it make what it sounds like? Kidding aside, I too have a V6. True dual is a little pricey, for little benefit on our V6s (discussed with my mechanic). I have the Y-split and it seems to work fine. Not sure the cost of true dual, X-pipe or H-pipe would make much of a sound or performance difference. I have heard good things about the Loudmouths. Myself, did dual Flowmaster American Thunders as I have a retro theme I'm sticking too and what's more retro than Flowmaster? If you DO go dual, I recommend swapping the V6 bumper for the GT bumper and NOT cut out around for the dual with the V6 bumper.
2005 Redfire V6 "Retro Pony"