I received a Giulia as an upgrade once in Rome FCO was fun to drive I thought. Also got the 500 Abarth once, very nippy (a little too nippy as I got pinged speeding). Also on that occasion someone took a liking to the Abarth badge on the side and took it off the car which Avis spotted and charged me €90 for.
Most of the time they kept giving me 500Xs which as with others above I found a pig of a car and terrible to drive. I once asked them at the counter why they kept giving me 500Xs as an 'upgrade' as its terrible to which the lady behind the counter meekly replied that in Italy they think of the 500X as a good car, that's when I snapped back into reality and realised I was trashing an Italian brand and should maybe temper my criticism.