I have one in the upstairs and one downstairs. Both APs use the same SSIDs, which I believe is recommended. Haven't ever had in issue with it. When looking at the controller you can see which AP a client is connected to and when. It seems to transition in a few seconds of going up or downstairs. In fact, it work well enough that you can actually track who is upstairs and who is downstairs by which AP they are connected to.