The tip on the WTCP soldering iron is temperature controlled. A PTA7 is 700 degrees. A PTA8 is too hot for most circuit boards, but it may be required for a board that uses lead-free solder. Wattage doesn't control temperatures. It controls how much the temperature of the tip droops when you touch it to a cold surface.
I bought a digitally controlled Hakko soldering station, and I love it. With the best equipment in the world, you still have to master the art of applying enough but not too much heat.