What are twin aileron servos and flaperons? Are they beneficial?

When a manufacturer or modeler talks about twin aileron servos, they usually mean the model has one servo operating each aileron on the wing and that the two servos are plugged into separate channels on the radio. Twin aileron servos are a very beneficial set up which allows the modeler more precise control of the aileron response of the model, as well as offering 'flaperons' -- the movement of both aileron servos in the same direction at the same time to act as flaps.