I started one once. It was a baby size quilt. I finished the quilting about half way. I hated it. I ended up ripping it all apart and starting it over with backing and batting. It is very difficult to quilt with. Make sure you look and watch a lot of tutorials to get the ins and outs.
In my personal opinion, It felt like I cheated my quilt. And, that is just my personal opinion. It sounds like many of you have enjoyed and like quilting with it.
Now, I do enjoy using flannel for backing. And, no, I don't use it all the time. Mostly with baby quilts. And, a lap quilt or 2,3.
Whatever you decide. Good luck and enjoy.