Hello,
If your concern is the 5GHz and the 2.4GHz devices interfering with each other, I think you should be fine. Even though not exactly the same scenario, some members in the forum have deployed dual band sector antennas (http://community.cambiumnetworks.com/t5/ePMP-2000-and-1000/Any-good-Dual-Multi-band-antennas-out-there/m-p/46485#M3920 for example). Having a non-synchronized 2.4GHz AP co-located with a 5GHz APs in the same tower should be ok, as they will be operating on different bands.
Regards