i suggest that you still bring it to the casa / mitsu specialist every 10K...

that's what i've been doing with my mazda, i take care of the usual oil, spark plug, filter change and leave the rest up to them. for our cars, they have this computerized engine diagnostic machine - that's better than your seat of the pants feeling about your car's condition.

plus, car maintenance isn't just contained to a change of spark plugs and engine oil. there are also things like coolant, battery fluid level, brake bads & fluids, suspension, etc...