I wash everything, including large yardage. Moda is usually very good fabric, but I have also found some that was very disappointing. (It was provided to me for a charity quilt; if I had found it in a store I would have bypassed it because it felt so flimsy.) I haven't really had a problem with the fabric bunching up in the washer or dryer. I press most pieces, but if it's a huge piece that will be a quilt back I don't press it. I learned a trick of loading the piece on the longarm. misting slightly with a spray bottle, and any wrinkles just vanish. (Don't I wish that work on my body? I'd be draped over that longarm in a minute.)