I agree with bringing your own thread and fabric. I sewed a lot of sequined, delicate and just plain ornery fabric long before I ever thought to try quilting (I just thought I'd give that a whirl a couple months ago). It is amazing how different machines will act with the same materials. Idealy you would take the same things to test drive all the machines so you would be sure you are comparing oranges to oranges. I always make a table with notes about how it handles each different type of fabric, thread, etc. I found one machine that sewed silk like a dream and ate tulle like a dog and it was a contender until that moment.