Both ways of supplying power to your right light have their merits. A light using an AC/DC adapter will probably be brighter but you will need a wall outlet or extension cord nearby. However, a light using USB power is likely to be more flexible in the locations you can use. It could be used anywhere with a PC or laptop or even permit you to Zoom or Skype while walking about by plugging into a power bank. Whether you choose USB power or an AC/DC adapter will depend on what you need to do when video conferencing.