Hmm. $3800 for no increase in fuel economy. But surely it should be faster than the Eco with 148 hp and 258 ft/lbs. Oh but no manual option...
My guess is that the real world MPG numbers will favor the diesel over the gas engine though.
Mine: 2008 Saab 9-3 Aero SportCombi XWD: 84k, Black, MANUAL
Gone: 2002 SVT, #1654
Hers: 2010 Focus SES: 73k, Ebony, Auto, Moon and Tune