Spark plugs, a cheap must do maintenence item

[07liftback]

So I recall reading in our forums that the spark plugs should be fine for over 100k miles and one need not worry about it. I finally got around to changing them as I've been having hard starts and lower mpg. The difference was dramatic, no more hard starts and much smoother acceleration. I have yet to measure the mpg and will report the results of mpg in a week or two. Next maintenance items will be both oxygen sensors, transmission flush, coolant flush, and fuel filter. Will report the results of each as I move along as far as mpg and how the car "feels"