Going on about the fuel effenciey.. Something slightly different..
Modern engines against the old ones are completely different.. In the old days it was really bad to labour an engine and its better to be a bit high in the rev's then labour (obviously not good for MPG but..)
So.. These days would you say (if one or the other had to be done) its better to rev the balls off the engine or labour it..
Lets just say you had two cars, both same age etc, one you laboured it everywhere, the other rev'ed it..
Which engine would die off first?
(forget running costs etc from fuel useage)