Fusible fleece is really wadding/ batting (polyester) with a fusible dotty bit on one side. It is like the fusible dots you get on regular iron on interfacing. It is a permanent bond. You use it for making things like Bags and home dec where you wan tthe wadding to stick to the fabric and may not be quilting. It isn't fleece material with a fusible on one side it is quite different and HAS to be enclosed or sewn in betweeen two layers of fabric.
Hobs Fusible batting is the 80/20 blend with a temporary fusible on BOTH sides and is designed to help you when layering and basting. It has limitations as when you iron it you have to have both sides covered with the fabric and it is less easy to keep the top and backing rumple free. I only use this for small things where I can startch the backing to within an inch of it's life! Actually I don't use it much at all unless I happen to have some left overs. I would always rather use a regular batting and 505 spray which lets you do the two layers at different times thus allowing you keep the rumples at bay.
I think there are two brands of fusible fleece: vilene which is a bit fluffy like cotton wool inbetween a firmer top and then the fusible back, but still a poly and then the pellon fusible fleece which is needle punched and firmer and flatter. i like both and use what I have available. Note that the pellon also comes in a NON fusible fleece so check when buying.
Hope that helps.
best becks