I have the Janome 6600P and have been FMQ on it and have had no problems with the machine - which I love (my technique still needs lots of improvement!). I have the blue dot bobbin case and mostly use Guterman threads and a 14 needle size - my machine seems to do well. The only time I have eyelashing and birds nests is when I forget to put the pressure foot down and I notice that almost immediately. Hopefully you can get yours running smoothly - I know that is frustrating!