Solder pots come in handy for other things too. Like desoldering high pin count connectors. You just float the board on the solder and lift the sucker out... As others have said, they're so cheap that it's hard to justify not having one..One warning, the cheap ones have power controllers, not temperature controllers.
Two tips (no pun intended) for soldering big things.
1: You are correct, a 100-150W, large mass, iron is what you want.
2: Preheating to 80 ish degrees C with an oven or hot air gun makes more difference than you think it will.
PK