We have just purchased a 90hp e-tec. Cant compare it with the 4 stroke but do know that the boat shop that sold it to us sold ALL brands of motor including the Yamaha 4 stroke so no barrow to push and they recommended the e-tec. The recommendation came as far as we know as unbiased advice - in fact they get more commission from the Yamaha people. The motor is virtually fume free, quiet, very quick to plane our 5.1 Quintrex Bowrider. Have only used it twice so can't comment on fuel and oil consumption but we are happy with our purchase. The motor is happy to go along at slow speeds as well as fast, we have motored up our river for an hour at 4 knots and it never missed a beat. The servicing costs are certainly worth considering. Either way, you really can't go wrong, we went through the same worries but made our choice and are happy with it. Hope you get some sleep soon!!