she gets about 26mpg average but some people get into the 30s and as for reeliabilty ive seen some dudes get over 500,000miles and more so I would say yes they are verry reliable and proven. Also they are verry easy to work on since they are inline 5 cylinder and the germans know what they are doing so everything just makes sense. I have fallen in love with the old Mercs. also the 240d has a 5 speed but it doesnt matter because everything is controled by vacume on these cars inuding the tansmision.