Completely depends on how you are trying to drive it. If you are doing some "spirited" or "aggressive" driving, then taking it through the Rev range will reward you with the powe you have available. Under normal driving conditions... I've read.. that while the engine is under normal operating temp (temp Guage reads 180) it's advised that you keep your RPM'S under 2,000, and after the engine is at normal operating temp, to keep it around 2,500 while moving (not at stop lights
). From personal experience, my car seems to run better, and even idle better if I have some spirited driving during my drives. I wouldn't suggest over revving or intentionally doing harm, but some fun is always ok!