very very few people in the US have 2nd generation 500's (nearly all are 1985's and older). I saw only two, including yours. Performance between a US 560 and Euro 500 should be about the same(in terms of hp) but I think torque is greater in the US 560. I will have to double check on that though.

500's burn slightly less fuel than 560's, so your numbers sound very normal.

I need to check what my current mileage is.. but its not good as I do 95% city driving (to work and back). When I took it to Niagara Falls and Vermont last year, I averaged I believe just over 18 mpg on the highway. This with 3 adults, 3 suitcases and some misc stuff.