Planning out my fermentation chamber build, and have a question about whether to get a dual or single stage temp controller. I live in Ohio so I will definitely need both heating and cooling. What I'm trying to decide is whether to get a dual stage controller like the Ranco, or I've seen some people just use a single stage controller to control the cooling and have a lightbulb constantly on in the chamber when it's colder outside. Then I assume the lightbulb will always be raising the temp of the chamber and the freezer will just have to cycle on every so often to keep it in check. This route would obviously be cheaper, but I was wondering what the main downsides would be?