Hi guys, yeah not a fan of stretched tires and I am already running 275s all round which is huge. I have already tried running 20mm spacers on rears and over humps they actually scrape quite bad. The problem is is this is not a full wide-body kit, i.e. they are stock GTR guards that have been flared to give a tougher stance which means the inner arches are flush with the 19x9.5+12 offset so although from a far it would occur that the wheels can indeed come out an extra 10-20mm, in fact they are just a snugg fit and anything further will surely scrape. I wanted a tougher stance hence the flaring so arguably if left stock, these wheels may look more flush on my GTR. But like you say, I like them they way they are and no need to push it out further for drivability.
I've posted a few other pics for you guys. Yes, a GTS's guardes if rolled or modified a bit may fit these wheels. Stock GTR definitely.