The trend seems to be going toward speed, automatic stitch regulators, and machine-on-a-frame quilting systems. Machines that were designed to be stationary on a table are often put on frames and suddenly become mobile. Some work well in this mode; some don't. There are some factors which should be considered when using a mobile machine.
2. If the machine has an automatic stitch regulator, it compensates for our uneven movements. As a result, we tend to go faster, placing more stress on the thread. There are some "workhorse" spun polyester threads which will work in almost any situation. They get the job done but they are usually plain and don't enhance the project. Some are quite linty. If you like the look of decorative threads, we give up a little in the strength department but gain everything in the beauty department. The key is to slow down. Some longarm machines have a speedometer which indicates the percentage of maximum speed. The safe speed limit for sensitive threads such as metallics is 30-35% of maximum.
3. If you use a semi-industrial or high-speed industrial machine, that machine was engineered to do high speed straight stitching with a tough, spun polyester thread on a stationary table. When we put the machine on a movable frame, select decorative threads, and hit the gas pedal, we're operating outside the intended use. It will work, but the key is to SLOW DOWN. Start out slowly and increase the speed to the point where the machine, thread, and movement work well together. When stopping, slowly ease to a stop.
Any machine should run a decent-quality-or-higher decorative thread. Remember to have the right needle size (usually a 90/14 or 100/16 on home machines), loosen the upper tension, and slow down.