What are you riding at the mo , what the main difference. I just bought the pro because they cost more than the sports and i figured you get what you pay for ...
Eibach pro
Thay a spot on ride quality is excellent. Thay will drop the car to look the same as the anniversary model. (about 25-30mm lower)
Sports will drop the car -40 mm plus but you wont get the same ride quality as the pros.
If you want the car to look low IE: So the tyre is under the arches: get the sports springs or coilovers - If you can put up with the ride.