Opt Lasers created several kinds of temperature control devices. There is no best TEC controller since each of them can be used depending on a situation. Choosing right TEC controller is important due to many reasons. One of them is heat dissipation. If your system is producing heat and its temperature is always going to be higher than desired then it is no need to use a cooling/heating TEC controller. The one with a cooling option will be absolutely enough. Some systems may need both cooling and heating. In a situation when the temperature of the environment is changing quickly or is lower than desired a TEC controller with full bridge may be needed. Additional functionalities like UART communication, size, PID algorithm or maximum current should also be taken into consideration especially when the system is expected to have an upgrade in the near future. Remember that using a proper TEC controller assures better efficiency of a laser diode and also extends its lifetime.