As announced in my introduction, I am soon to be the owner of 2012. Abarth 500c EsseEsse. Since the dealer I'm going to buy from has couple of Abarths in his front yard, I have taken measuring tape today with me and compared standard Abarth 500 and Esseesse concerning the height. So here are the figures for ground to wheel cutouts (fender openings) in centimeters:
              Standard A500      EsseEsse
Front               62                    61
Back                66                    63
So yes, Esseesse is 20mm lower on average as advertised, but more in the back than in front. Although doesn't sound much, when seen by naked eye it is much more pleasing.
Hoping this helps someone interested in Esseesse suspension.