With either muffler I think you will be happy. The Magnaflow'* have a raspier bark verus the Flowmasters which are a bit deeper at idle.
I have Flowmaster'* on my F-150 that I replaced Gibson'* for and I like. The Gibson'* just didn't have a throaty sound on the F-150, but I liked them on my 92 Exploder.
I had Borla on my ZX3 and that was anoying! Sounded like a ricer, but with a bass. I didn't like my neighbor then, so I left it on.
So from this post I'm sure you are confused and annoyed. The main thing to take from this is that not all mufflers and exhuast systems are the same, they all sound different on different vehicles and with different mods, and its totally up to you on what you hear and like. It'* not uncommon to take off a new muffler to change it up to something else if your not happy. Talk to your exhaust shop and see if they would be willing to clamp one or another on for a test drive before they weld it and your buy it.