Swift sports 1.6m specs
Power 125 bhp
Torque 140 Nm
Acceleration 8.9s (0-100kmh)
Top Speed 200kmh
Transmission 5-speed manual
Kerb weight 1,100kg
Fuel tank capacity 43L
Brakes (Front) Ventilated disc
Brakes (Rear) Disc
Swift 1.5A Specs
Power 101 bhp
Torque 133 Nm
Acceleration 11.7s (0-100kmh)
Top Speed 170kmh
Transmission 4-speed automatic
Kerb weight 1,080kg
Brakes (Front) Ventilated disc
Brakes (Rear) Drum
The swift sports and the normal swift is quite different as the swift sports is build for more performance while the latter is only a normal hatch. Although both has good handling but the swift sports has a better/stiffer suspension and better brakes. The swift sports is better equipped with sports seats and 16" rims and twin exhaust pipes but all these are minor issues since there are aftermarket products to be sought after.
Main difference is the chassis, in the swift sports, the chassis is enhanced as compared to normal version and also it has a much better platform for modification as it comes in manual. If you are just looking for a normal hatch and maybe the looks, take the normal swift but if performance is what you are looking for, then swift sports is definitely between the 2. i hope these can help clarify your doubts.
ps: i forgot to add that it has 6 airbags compared to 2 from the 1.5A and also you might want to check out this video from fifth gear on youtube about the SSS:
YouTube - Suzuki Swift