From what I understand, wattage isn't about temperature. An iron with a higher wattage will heat up quicker and maintain a more stable temperature; the temp won't drop as much if you're heating a big joint. But like others are saying, if you can find one get one where you can control the temperature like the Hakko. They heat up in seconds. I keep mine around 330-350degF for most soldering, but if I'm soldering something that requires a lot of heat like the ground on the back of a guitar pot, I'll crank it up to 500-600deg. Or if I'm desoldering a part and don't care if I ruin it.