I would just go with GTLW for the time being, especially if you are going to keep it NA. It is a very high quality exhaust, you basicly will get to enjoy it almost for free if you ever decide to sell.
I really enjoyed my GTLW when my NSX was NA. I complained about the GTLW exhaust note years ago after SC, due the the change of exhaust note. Alasnsx has a better back to back comparison video.
The pitch are quite different between the two. The supercharger whine is also significantly less noticeable with GTone V5.1 as you can tell. To me it is a pleasant surprise that they actually compliment each other and made the SC whine significantly less annoying.
Some flyby comparision (GTLW):
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Not a flyby, not my camera ( GTone V5.1):
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GTLW taking off:
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GTone V5.1 taking off and flyby:
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