I 've configured 2 E500 as base/client in order to create a mesh link at 5GHz.
There is also a second WLAN for users (both 2,4 & 5 GHz).
After creating the mesh link, i observed that the power of 5GHz Radio becomes automatically very low (3 dΒ) at client, and the perfomance of the AP (client) is bad.