I found a older set of NT03 from my old evo. The size is 18x9.5 with a +40 offset.

I prefer to run non staggered wheels since it's easier to rotate and not worry about flat tire issues. Will these work mount of my IS350 F-sport without any rubbing issues?

 

That will fit, but what is your tire size

 

Any suggestions what would work without any fender rolling and such?

 

I don't have an answer, but I appreciate your comment about staggered fitment. In addition to the rotation issue, there's also the problem of understeer. Taller, narrower tires up front means that the car will push. Other than for looks, and off-the-line traction, what's the point of inducing understeer every time you bend the car into a turn? Safety? Sorry, but I don't get it.

At some point, I'd like to square my set up too. Like you, curious to see what wheel/tire size fits up front.

 

I would run a stretch setup with tire size 225/30-40/18 and that for sure will fit without rubbing if lowered.

 

If all goes well, I'll be getting a 350 RWD next weekend. Once it's home, I plan to put on the tires and wheels off my current STI which are Enkei PF01 18x9.5+45 with 265/35/18 Dunlop Star Specs just to see how they fit. I don't think the wheels will look good on the IS, but I simply want to see how they fit.

 

What if I will be at stock height?

People are telling me that it's going to look awkward being too far extended and I may need to roll my fenders with 9.5" wheels on a squared setup

 

I just tried to mount some 18x9.5+45 wheels with 265/35 Dunlop Star Specs on my 350 F sport and they won't work on the front because the inside of the tire hits the knuckle. I spaced them out with 7mm of washers, and it barely cleared. With the spacers, they were poking out quite a bit. I should also mention that the Star Specs usually run wide compared to other tires from what I've read.

The rears, on the other hand, didn't look too bad.

 

That's a pretty wide front tire you're mounting! I would be surprised if they didn't rub!