unfortunately for the SI it can't hang with a BRZ... read the article, SI was on high performance summer tires, the BRZ was on the all season prius tires ... personally? i obiously prefer the SI overall as that's why i bought it, but if you look at it from a pure track perspective, the SI can't hang with an equally equipped (proper tires)BRZ, though this is a great article, and shows that the SI does have some stones, more than people assume