The drop-in bobbin of the 201 means the thread takes a 90-degree turn at the needle, and people say that can cause a problem with FMQ. (The 15 bobbin is mounted vertically, so the thread travels in a straight line.) I can't confirm or deny this claim; I've only done a little FMQ. I can, however, vouch for the 15 as a user-friendly machine. Thread capacity is a wee bit better, too - fewer bobbin changes when doing FMQ.