many on this board report that their machine will only sew with certain thread, so you need to find that out about your machine. Otherwise, like fabric, get the best you can afford, I love Superior brand because it is high quality and seems to work on everything for me. I also use Mettler and Gutterman a lot, especially if they're on sale. That being said, even those brands have several versions and you need to make sure you use a machine thread and not a hand quilting thread. The needle type also makes a big difference...if the hole in the needle is not smooth enough or large enough for the thread, the thread will break more often. Superior, and several quilters I know and know about say that if you always use a topstich needle you can work with any type of thread because the hole is larger and smoother and the scarf of the needle is large enough to handle any thread except the largest (jean type) threads.