Sport models are lower yes. 4cm drop isn't going to cause much issue to be honest, if you have speed bumps around your area that will probably be your biggest problem, but for ease of mind why not check the clearance of the bigger bumps in your general journeys, just get out and see how close it is to your bumper when above it. If it's more than 40mm. Go right for it.
I wouldn't check this at rush hour though. Try late at night with minimal traffic on the road.