I tend to use muslin in most cases - a good quality muslin. I find it easy to work with. For doll quilts or small projects, I will use a coordinating fabric. All a matter of choice.

as a backing material, background material

There are a lot of different grades of Muslin, the last I bought was from Hobby Lobby, 45" wide, bought the whole bolt,40% off, use it for everything. I've seen the wider width there but didn't seem as good weight. There is some that is not worth taking home, just have to look and feel. I, also use matching fabric as well, but Muslin seems comforting to me, and no way would it wear out any sooner than regular fabric.

Mae

I like using coordinating prints. as far as the cost, I always use my 40% off coupons from Joanns.

It depends on the item I am making, but I try to use a very good quality muslin regardless.

I use muslin for backing a lot. I be sure that I buy good quality muslin. After all who sees the back of a quilt.

I have used muslin. I also have used pretty sheets for the backing. I use unbleached muslin sometimes, if I am wanting the quilt to look older. Just all depends on what type of quilt you are making.

I've been paying more attention to what I back my tablerunners with. I like to make them reversible so I end up with two for the price of one. Sometimes I end up liking the back more than the front.

Yes for wallhangings and chair covers. Generally prefer to double side my quilts. Detailing of the quilting for one side means the other side has to be forgiving of the design.

I used to use muslin but now I sometimes uses other fabric and sometimes quilters flannel for warmth.