I've heard of a few water pump replacements at perhaps earlier than expected mileage. What kind of lifespan is typical for our water pumps? Does the 2009 model still have the auxiliary electric pump? Typically my approach to maintenance for something like a water pump is to replace it as preventative maintenance somewhere around the halfway point of the engine's expected lifespan as it is typically inexpensive, not that hard to do, and far less annoying as scheduled maintenance than as a roadside emergency on a long trip. Thoughts?