With its strong motor and grippy tyres the SX4 is a fun car that is quite a hard charger. The motor may not be as free-revving as the Fiesta's, especially in the top part of the powerband, but the Suzuki matches the Ford for straightline performance on the track. (0-100 performance is not the same thing). But though it has wider 205 tyres, the SX4 can't muster the same levels of grip as the raised suspension and tall profile of the tyres lead to lots of body roll and erosion of grip.
The SX4 can't carry as much speed into a corner, the car drifts a lot and the steering doesn't have the same amount of feel. It especially loses a lot of time on switch back corners when the road turns the other way. However, the heel and toe position on the SX4 is very good.