I just found this on another site.
A couple folks warned that while the Featherweight can FMQ, it was not built for such continuous sewing. It can overheat the motor. So, I think it depends on how long you stitch at a time without some cool down time. This is because a FW is a belt driven motor and will tend to overheat if you do high speed FMQ. You can use it but for short periods. An older Singer with a gear driven motor like a 401 or 501 will FMQ much better.