I have a 4" muffler back system, I am going to bag it for something better & possibly a bit louder. Browsing I came across a 4" SS magnaflow system for $380, was about to get it and then came across a $375 - 5" aluminized system that has a 4" downpipe then goes 5" 2 feet down to a 5" muffler and out. The magnaflow has a 3. 5" dowpipe, then goes 4" the rest of the way, but it is stainless. Both are mandrel bent. Which would you choose? Whould the 5" have better performance? Im pretty sure it would be louder too correct?

