Lowering Standard 2004 A3 on RS6 alloys?

[Ports]

Hi Guys,
Im sure your all fed up with the amount of lowering questions, but i cant find the answer im looking for.... how much would S-line springs lower my standard A3 1.9 tdi which will eventually be on 18" RS6 wheels. Dont want to spend alot of money, if not the S-Line's which wiould be another good spring to make the car sit nicely.

Cheers
Adam

 

[nally]

sport is 10 mm lower
sline is 20 mm lower

i think sline would be ok and you can prob pick up cheaply