Originally Posted by Srenity

That setup will be fine as is. Both the front and rear tires will be a tiny bit stretched compared to factory but not much. You only added half an inch in width of the rims and kept factory tire width. The offsets are pretty safe and plenty streetable on the swifts. If you want to be more flush in the rear you can add a spacer like mentioned but it should look good as is. The Pilot Super Sports are great tires. The shop did not do you wrong in your setup. They just leaned you to a slightly conservitive set up for the street. I think once you put them on you will be happy with the setup.

The stretch is not going to be bad enough to have any of the ill effects that you are scared of.