Soldering iron firmware is useful for closed-loop temperature regulation and viewing the current temperature, but can be dangerous when the code goes wrong. A while back I found and fixed a bug that would cause button handling to malfunction after 49.7 days of uptime being plugged in, which could be dangerous if anyone actually plugs their Pinecil in for that long. Also I find that the two-button input is difficult to configure such a complex iron with nested menus, selectable options, iron on/off and temperature control and boost, and I sometimes end up mistakenly setting my iron to a temperature higher or lower than intended.