Nick,
I'm in the exhaust mod market too, having finished my front end mods. I plan to go with headers, I think the only options for 2500 Ram 6.4 are ARH & AFE. I'm doing this to prevent the poor design stock exhaust manifold warping and breaking attaching bolt heads. At 36k miles, I know I'm in the danger range.
Stock manifolds are extremely restrictive, one of the poorest & restrictive designs I've seen - a horizontal tube with ports and thin flange = high backpressure, warpage, broken bolts, exhaust leaks (EPA should be all over this, but isn't). FCA refuses to address the bad design except for fix-as-fail, repeatedly.
I plan to put on ARH & cats, but need to save for it and do in spring. My question is, when I do this, will a lower restriction muffler make the exhaust too loud? I was going to use Solo Performance MR400 drop in muffler assembly, as the least loud performance retrofit.
Please respond, I think OP would appreciate response here instead of a PM. Once I decide we can PM pricing. Thanks!