I've seen it once where someone rounded out the GT bumper and TBH, it looked weird. I mean it looked good, but seeing as I am just so used to the cutout being there, seeing anything else just looks weird to me. One of those things where when you look at something for 20-25 years, it just looks different when theres a change.
I run my front plate because I've had some negative interactions with cops in my youth for total BS things like this and I am just too old for that BS now. My Fox has a cool vanity plate I like to show off, but on my SN I could care less if it has a plate up front. At this point, i'm so used to front plates that it sort of disappears. It's when I see things like plates on the dash, or mounted offset or low on the bumper that it looks different and stands out to me.