Yes, SmartDesk Core and Pro can both go with the XL top. If you are currently using the classic size top and would like to upgrade to the XL one, you can simply extend the crossbar to both edges to fit the length of XL Top.
After removing the top from the frame, loosen the 4 screws in the middle of the crossbar to extend the crossbar to both ends, then tighten back the screws and attach the XL top on it.
