I've been using Staflo half and half with water. I like to partially dry the fabric first to keep it off my iron. When I used the dryer I found some stiff wrinkles. Now I spray the fabric over the tub and hang it over the shower rod (with a mat or towel under to catch the drips). This makes the fabric very stiff, and so far, it's really helped me with free motion quilting. I always wash after the quilt is finished, it's nicer not being so stiff when you give it away!
It's fun to try different ways and see what works best for you! Love the 'NO Quilt Police' rule!!