Because of that, as long as we've been homeowners I've had someone out every spring and fall. Several years back at our old house the fall check caught one of those aforementioned potential issues when a voltage check revealed a circuit board on the verge of going bad. Had it not been caught when it was it's very likely we would have lost our heat and needed a far more expensive emergency service call to fix it along with sitting in the cold. (It was also caught while the system was still under warranty which was a plus since we only had to pay the labor cost to fix it.)
While I held off for the first year on our new house because of the warranty, now that it's over I had James River Air out this afternoon to do the winter check up. While I figured everything would be fine given the young age of the system, the peace of mind in knowing for sure was worth the expense.
On a related note, if you're served by Dominion Virginia Power they offer a heat pump tune up rebate program that will cover the cost of the service if you qualify.