Most of my quilts have been tied with embroidery floss, all 6 strands, although most of my quilts have been lap sized and donated, I did make one for a friend for last Christmas that I tied, it's a Queen sized. It turned out fine. I don't think that tying or quilting makes a difference as far as warmth is concerned. Tying really isn't hard to do, but I do tie mine a lot closer than most people.