IME, lunch portions are a great value and ample, but dinner portions are even larger. Some WS restaurants do fairly significant menu changes between lunch and dinner so its worth checking to make sure the lunch menu meets your expectations. Lunch entrees are often simplier (Le Cellier offers a much more sandwich heavy lunch menu than their fancy entree loaded dinner menu, San Angel Inn used to, at least, have a much more Tex-Mex lunch menu than its dinner menu). But some restaurant have near identical menus and portion sizes at lunch and dinner (IIRC Teppenyaki does, and now charges the same price).