So i have decided to go with magnaflow 14815 with coupe midpipe.
however, i saw a clip of g35 with duel exhaust. man, it looks so great.....
this made me have a mixed feeling.
any suggestion?

Get what you want the first time.

The Magnflow Y-Back exhaust is a waste of your $$! You won't realize any improvement in sound or throttle response. (been there) If you're looking for results from your exhaust start with a set of FI high flow cats which will free up the restriction found in your OE cats and add extra HP. If you're looking for more sound step up to a dual cat-back exhaust....Stillen or Motordyne. Not the cheap replica trash some members opt for....Gary

Just leave it.