I've used vellux, but switched over to fleece after maybe a year or so. Fortunately Miss Satin was not a digger in the way Nancy describes, so it worked for her.
It's similar to fleece in that you can cut it to size without worrying about edges fraying.
What I prefer about vellux is it's more lightweight, easier to clean, and dries faster than fleece. It doesn't soak up water like fleece, so if someone spills their water dish or pees on it, the fluid mostly just sits there and evaporates... doesn't absorb and spread dampness throughout itself (or to the hedgie who's now underneath their blankie that's underneath the liquid).
Why I switched is that, after awhile, spots do get worn and you can see the inner mesh. At that point, it's a potential danger. You have to replace the vellux more quickly than fleece for that reason - so it's more expensive in the long-run. As it ages, you have to spend time standing around and examining it each time it comes back out of the wash to make sure it's still good/safe. I'd rather spend my hedgie-time with my hedgies, rather than with their blankies. And, of course, there are more cute colors and patterns with fleece than vellux