What particular unit are you talking about? You said open air, I'm assuming this means the gas powered one, not the wired one? The wired one is a dirt cheap 30 watt soldering Iron, nothing special at all. The gas one is capable of a bit more, but both require a bit of finesse as they're not temperature controlled. Either one will work just fine for general soldering work. You'd have to define 'thickish wire' to see if it'd meet your needs though. I would not use it for PCB work, you'd want a temperature controlled unit for that, the gas unit could be used for heat shrinking but you'd have to be careful, it being a small flame helps.