Italian pilots fly same as they play football. Cheating, lies, ... I´m really fed up of hear " TWR, in 2 minutes we arrrrrre rrrrready for push-back, Is possible an extension of the slot? WTF!!!!!
I'm an Italian ATCO and work with (well, the right word would be 'for', if you believe in the 'service provider' thing) Italian pilots on a daily basis, so I know what you (think you) are talking about. Yes, there are some cheaters, but I've found that 99% of the pilots will underestimate their taxi time when they have an expiring slot, regardless of nationality/airline. By the way, have you ever tried saying "no" when it is clear that they won't make it? Works every time for me and that doesn't make me any more stressed. Actually, I wouldn't be doing any favour to my colleagues of the following sectors, should I let an aircraft depart outside of the slot tolerance window.
As for the Brits, in my experience they are amongst the most polite crews around. Clear, smart and cooperative. Oh and believe me, none of them has ever burped on my frequency following a drinking session in a Manchester pub - yet!