I think JOUY31 might not have tried the Alitalia one yet ;-) Everybody with a Skyteam Elite+ card may enter there but it is very, very minimalistic. A coffee machine, some booze and peanuts.
The best lounge, imho, is the Olympic one. When flying CSA they give out access to this lounge. Includes showers and proper food (Spring rolls, warm potato/bacon snacks, sometimes chicken). And of course sandwiches and a whole array of traditional Greek sweet pastries.
The one thing I am still missing tho is a proper smokey souvlakia stand. That would be good!