Depending on the size of the tank, I strongly recommend investing in a redundant controller. InkBird is kind of the industry standard for low to mid range controllers. You set the heater to heat up to 75°, and then set the Inkbird to turn off at 80° -- if your heater gets stuck "on," the inkbird will kick in and turn it off. You can get Inkbirds for as little as $30-40, and some of them also have WiFi capability.
And if you're going with a really big tank, or lots of expensive fish, investing in something like an Apex (or even an Apex JR or EL) can be worthwhile, especially for other features in it. Some of the other competing controllers will be fine, too, but I'm less familiar with them. The Hydros gets good reviews, and has a lot of WiFi capability. The GHLs are awesome, but they're only slowly becoming available (and compatible) in the US. (Of course, all of these devices are little more than fancy on / off switches if you don't know how to use them or don't use them to their potential).