I can tell you from personal experience that Glintwerks is light years ahead of my old tried and true Light Sweep, which began its life as part of Final Effects Complete. I often used light sweep as a way to pass a diagonal soft bar of light across text or invigorator animation movie, but find Glintwerks is a whole lot more powerful, yet easy to use and fast to render.
Essentially, you get a powerful Photoshop-style gradient editor that includes both color and transparency, with a library of cool presets to get you going quickly. You can animate the resulting gradient across the face of your After Effects layer, whether it's text or something else, but that's just the beginning. You can add some extra special effects like texture maps revealed in the animating glint, and using the glint to reveal or hide the layer. You can add a glow to your traveling glint with one mouse click. No traveling mattes required! All of this and many more features in a fast, easy to use plug-in.
I 'm proud to say I spent several days as part of the team demonstrating Glintwerks and the whole suite of Zaxwerks software at NAB last week. Very cool stuff!