It would depend on your situation. As explained above you can have more than one tagged vlan per port and only one untagged vlan, but how many devices on the vlan? More than 200-300 devices could start impacting performance depending on utilization, ,protocols, congestion, drops and other statistics you can find on the switch. I have 22 buildings (several are 3 or 4 floors) and I configure a separate vlan per floor and the device count is 50-200 devices per vlan.