Problem with Koni springs in that kit is that nobody seems to know what spring rate it is exactly, and same goes for the Bilstein kit as well. I assume since it's oriented more towards mass crowd rather than hardcore enthusiasts, the spring rate will be pretty mediocre at best, and it's mostly for the drop. Expect something C springs-ish. I would not go for it, because tuning the car's suspension with unknown factors is like defusing a bomb with out instructions.