I have seen a few people here talking about putting 15 inches on the ST. I currently have a 2012 Fiesta SE. I have 15's on rims for the winter and they should be good for another 1 or 2 winter. If I remember correctly, the offset of those rims are 38. The only that was bothering me though, is that right now, on my winter and summer wheels, the caliper is kinda close to the wheel, and I believe that the brakes of the ST were bigger than the base Fiesta. After looking a little bit on the web, it seems the base Fiesta brakes are 10.2 inches while the ST ones are 10.9. So my question: how are the 15 fitting on the ST? I plan on buying the ST probably before the end of spring or during the summer, but I would like to make sure that my current tires could fit on the ST.