My experience with using a serger is that it needs several cones in order to make the over-lock stitching system. In this use, there are several threads, but I do not feel the weight of the thread is inferior to any other threads. I cannot imagine anyone making a mistake by using it since so many people have used it for many years. I think it is more preference. It is a choice to say a person would say they choose to use only the more expensive threads. If you consider how many stitches go into a quilt while quilting it, one broken thread is certainly not going to be a disaster. The quilt will NEVER fall apart. I cannot understand that theory.
We all have ideas of what works for us and because I make my quilts to give away, the price of thread is taken into consideration. And I doubt the recipient would know what kind of thread was used.
June in Cincinnati