From a number of sources [Eurocontrol ++] we have collected the following:
Advanced Surface Movement Guidance & Control System (A-SMGCS) is in an operational test phase at CDG, VIE and MUC but has also been installed (or are under installation) at a bunch of other european airports like: CGN, LYS, TLS, MAD, Barcelona, Oslo, Stockholm, Prague, FCO, Malpensa, AMS, Riga, LGW, LHR, BRU, FRA, HAM, DUS, Palma De Mallorca, CPH, Zurich, Geneva, Paris Orly.
As I understand it, Eurocontrol likes you to turn it on from the time you request push.