The WRX has been been blessed with coil on plug technology since it's inception. This means no power robbing spark plug wires in your engine bay that you have to replace every 30,000 miles.
Subaru Coil Pack Repair | There is a downside though. The coil packs are mounted right on the heads of the engine. The very hot engine. Over time, the plastic becomes brittle, and when handled, they break. The electrical connector is even more prone to heat related failures / breakage.