I got 33mpg over the 6 months I had mine - Jan-Jul. When I got it serviced and the oil replaced with a good quality 5/40 fully synthetic, I gained about an extra 2 mpg straight away. My engine had 136k on it by the time I traded it in but ran as smoothly and quietly as an enigine with only 36k on it.
Just check that it's been serviced regularly, had the cam belt replaced (at least once) and is generally well looked-after