HCH is one of the most hated hybrids in the US. See this thread below in hybridcars.com. In fact they seem to have reduced the expected FE figures from 50 to 40 in the 2008 version. Even I read an article in AutoBild India where there is a shootout between Civic 1.8 and HCH. It claims 13.5 as the average mileage for HCH. I think its too less for a car worth that much.
Honda Civic hybrid poor gas mileage | Hybrid Cars