Bosch Platinum +4 Spark Plug
For the vast majority of drivers on the road today, the Bosch Platinum +4 can be considered the best all-around spark plug. The Platinum +4 achieves its high performance by employing four (as opposed to one) yttrium-enhanced ground electrodes. This creates a powerful, long-duration spark which is better suited to igniting the fuel/air mixture in any engine, high performance or not.
This spark plug requires no gapping or maintenance - you can simply install these in the engine and 'forget' about them until the next time you need a tune-up. The price of the Bosch Platinum +4 falls neatly in between a traditional spark plug and Bosch's own Platinum IR Fusion model, meaning that these performance spark plugs can even be considered relatively affordable.