Our Sport has around 12K miles on it. Around town, we average right around the EPA 16. Our city driving is worst case scenario as it is a small town and all of your driving is short hops, mainly of 1 mile or less. Highway we are averaging over the EPA 22, and have seen as high as 25-26. This is on a 240 mile roundtrip from 5500ft to 1800ft to 6200ft to 1100ft and everything in between. This is in 115 degree heat, and 10 degree cold.
Frankly, we have been thrilled with our mileage. Yes, the 25-26 is with trying to get mileage, so we were not going over the speed limit. However, driving normally at 5 above the limit, with all of the mountains and curves we are dealing with, we still average over the EPA highway mileage. This even includes a short stop and go (stop signs) and a stretch of 75 (we do 80). Also, there is often a little "fun" involved (chasing a Porsche through the curves), etc.
As long as you are not hot dogging it all the time, the Beastie (our affectionate name for her) will easily pull the EPA mileage.