I have an 08 5.7 Hemi. I put on Flowmaster Super44 Muffler in place of the huge stock one and the cut off the stock resonator as well.
It is also common for our Hemi's to have a leak at the engine / exhaust manifold. Some times the manifolds warp, cracking the head off a bolt and letting exhaust gas escape. Makes the truck sound kinda old and hissy. Have your exhaust guy check all molts on the exhaust manifold, look for cracks too. OEM replacements, I believe are like $120 per side. The labor to change them is high, very difficult to get to.
I don't have a video of my exhaust, however this is the one that sold me. Sounds just like this (understanding that cell phones don;t really get the exact sound). I think she sounds like a beast, similar to alot of the Dodge Ram 1500 5.7Hemis with loud exhausts.