Great post by Keith Miller - this IS a 'thing' with AP vendors and Wi-Fi Design Tool vendors. No one is to blame, but you NEED to understand how your AP vendor calculates Tx power in the dashboard, and how the Wi-Fi Design Tool vendor calculates Tx power in their design tool. Sometimes they are exactly the same, sometimes not. This is just a warning to be careful and learn how your tool works with your AP vendor of choice.