Hey there,
I came a cross a set of eibach Golf MK5 springs that were replaced for a lower set. I fitted these to my Cupra and fitted perfectly...after a few days unpleasant cracking a rattling started so I had to place a water hose tube at the top. Then I got a set of eibachs specifically labeled for Seat Leon and installed them to a friends car...difference was evident. in mine the ride height between front and rear was not even an my friends car was once centimeter lower...
I would that if you have the money, go for the specified equipment, unless you come across a really good deal,
cheers