The Dynomax cat-back, non-stainless, is ok. I've used that and it seemed a bit louder than the Borla I am using. But, it didn't last!
And the Borla is straight-through, too. I'm still trying to figure that one out. Must be the baffling material Borla uses - extra dense stainless steel brillo pads
WOT though, the Borla is loud. I sometimes go WOT on On-Ramps and people already going 65 on the highway move over to make way for the "champ car" they hear about to merge.
Frankly, the Borla is livable and durable and looks good, too. So I am sticking with it.
But, I could handle a muffler that gave the better flow and allowed you to wind out the 4Banger in the 3000-4500rpm range without waking the dead/rustling the cops in urban areas. I know they make mufflers like that for car like the ford focus, etc.