If you go into Superior Thread look around their site. You can use anything from there with the piece of mind that it will be fine for your machine. I got as a gift 13 large spools of the Alex Anderson line Master Piece. Each spool is $25.00 for 3000 yards. I don't think I will ever run out of thread. I have also used Libby Lehman Bottom Line and I love it for piecing and quilting. Also bobbincentral.com has some excellent threads. The good thing is that you can order a sample and they send you 4 or 5 bobbins to try. they will not fit your machine but you can transfer to one of your bobbins. On the same package they sent me a cone of a wonderful thread and it was enough for a wallhanging.
Aurifill is a great thread but I would not limit myself to it. Mettler and Gutterman are very good too.