I don't think it will make a noticeable impact. The OEM exhaust is heavily baffled. I replaced mine as well with a Magnaflow unit and finished the exhaust with a Vibrant single in, dual out muffler. The exhaust note is decidedly sharper, but I can't detect any drone from the cabin. My guess is the catalytic converter in the mid pipe absorbs a lot of engine noise.
Plus side is an aftermarket resonator will be easy to install in that aft exhaust piece should you be unhappy with the results. And they're cheap.