When setting a Guest WiFi I prefer to have the guest WiFi interfaces (2.4 and 5GHz) attached to a separate (new) bridge and then make sure I have the right firewall rules so that the guest network has access only to Internet.
I recently used the Quick Set option for Guest Wifi and I noticed that it bonds the guest WiFi interfaces to the "main" bridge and the guest WiFi clients use the DHCP server of the LAN. I noticed that the filtering is done via bridge filters.
Which approach is more recommended? What is your opinion?