This product is trash. Do not buy. I don't understand the positive reviews. Maybe the different sizes all share reviews. My review applies to the 400 disc size.
Details: The build quality is mostly fine. The issue is with how the pages are bound together. They aren't individual pages free to compress and expand on a plastic ring/slide like some other disc binders. The designers didn't get the amount of extra fabric to compensate for the thickness of the discs correct. With enough patience you can use every last page, but you won't want to. Doing so also makes it pretty much impossible to browse through the pages. Another reviewer posted that you can't close the binder if it's 100% full. It's not impossible, but... you won't want to ever take it that far.