I have all the aforementioned props, so I'll risk boring those-who-know with descriptions of how they differ. Nerd's backdrop and the RDNA Infinity Cove are backdrops, like hanging theatrical scrims, on which properly proportioned images can be projected as "texture." The advantage is that the props curve forward at ground level so that figures' shadows will show in the scene. It's a cool solution, but has limitations. I use the Cove extensively for abstract backgrounds. I've found it difficult to calibrate my own digital photos to work with Nerd's tool, although there are now lots of textures for it that work. The DAZ Cyclorama offers what I feel is a superior solution. There is a truly level "ground" which is textured to match the background prop, which is a semicircular scrim. It comes with moveable transmaps for additional elements (rocks, trees, bushes) for each of the default scenes (beach, field, and forest, all of which are quite nice.) The Cyclorama works well in animations, due to the fact that there are elements at different depths. Have you ever seen one of the very early black/white "Popeye" cartoons? The animators used similar tricks to simulate depth. The new freebie environments work pretty well, although they don't come with additional trans-scrims or light sets, no biggie. Only prob I see is that the curvature on the brick wall is too obvious in an animation, although it does make a beautiful backdrop for still images. The RDNA CycloDrop is similar, although the available textures are more abstract. I haven't seen one yet that simulates an actual realistic environment, although the recently released skies pack includes some beautiful images. The thing I don't think people realize about the Cyclodrop is that it comes with several layers of transparent scrim in front of the main, solid drop. They can be moved individually, furthermore, different images can be applied to each. You can get some very cool effects by playing around. I'll post an image or two that show some effects I've been able to achieve with the free props. I strongly recommend getting the two free background props from RDNA and experimenting. I've been very happy with the DAZ Cyclorama as well.