I agree about learning how to use it without any temp/fan systems first. Do you have other smokers? If so, consider the Stoker System as well. The system will allow you to purchase one controller and add fans/sensors for multiple smokers. For a 22 1/2" WSM, I recommend the 10 cfm fan.
If you do not have a second smoker, you may soon after you start enjoying your WSM. Another reason to consider the Stoker.