There are times when it’s easier to edit and add information to a WordPress post or page using the Text editor, as opposed to the visual editor. For example, when using DIVs to layout images and text together. The challenge comes when you move back and forth between the two. Many times, this causes you to lose formatting.
Raw HTML Pro is a plugin that allows you to protect your HTML formatting from the Text editor when you move from Text edit to the Visual editor. When working with clients, I frequently ran into this problem when they took over their sites and started editing them. The $15.00 price was well worth it to keep my sanity and reduce support calls.