I had 235/50-18s on 7.5in Stern wheels on my Sebring and they fit very nicely. I was also basing the tire choice on a post in the aftermarket wheel/tire thread showing a 2012 (lowered) Focus and listed 235/45R-17 on 17x7.5s and I thought it looked great.
2012 Kona Blue SEL Hatchback "BlueJay"
K&N air filter, snorkel delete, Magnaflow exhaust
"Listen to the noise this thing makes. I'm only this big but I'm a Lamborghini, really I am!"
- Jeremy Clarkson