I have stored quilts, down comforters and bedspreads in space bags. I have never had any problems. I do take them out once a year and fluff them. I've never had a plastic smell or any smell for that matter. There are many different manufacturers of space bags. They are expensive but get the name brand ones. The cheaper ones may be the smelly ones. Make sure your quilt is washed and dried without fabric sheets before you space bag them. I know a lot of people do not wash their fabric before sewing it so maybe that is some of the odor when it's taken out of the bag. I also space bag a lot of my extra fabric, especially fleece. Just keep in mind that little bundle of space bagged fabric still weights a ton. I put 45 yards in one and then couldn't lift it without hurting myself.