I have a Hub and a Hub Express. Both show the MAC address of the tower I a connected to at any moment via the Web GUI. The Hub Express has a Log that shows if it is switching towers. Usually it is not and 99%+ of the time it's on the same tower MAC address.
Visit 192.168.15.1 and use password CLEAR123 or motorola
Then after the wizard is done setting up your preferences you can see the modem connection information. scroll down and it will give you the list of BSIDs and show you which one you are connected to. With the Motorola modem every 8 CINR points in difference will force the modem to search to connect to the very best tower