If you want to find all you ever wanted to know about threads, needles and tension look up on YouTube a video called TNT by HandiQuilter. It is The best info out there. I have dozens of serger cones but I would not use them in my long arm for the same reason many people already mentioned - it breaks too easily. I use 50 or 60 wt thread for most of my quilting. It is polyester, but much, much stronger than serger thread. Yes, you can use whatever you want, but you have to ask yourself if you are willing to put all that effort into something that will not last. The only time I can see using serger thread in quilting is if you are going to quilt really densely, on a wall hanging, or something that will not be handled on a daily basis. Unfortunately, really good quilting thread tends to be expensive, but it is totally worth it. When I am in the zone, and quilting, I do not want thread breaking all the time. It is distracting, and bad for my mojo. I hope this helps.