I have the 6600 as well (and not sure how it compares to the 11000). I've heard about the blue bobbin and thought "need to get one of those". In the mean time I kept practicing. I have not a single problem with FMQ that I can't attribute 100% to a different problem (thread, needle, or operator <g>). I just finished quilting - very heavy quilting, with some thread painting, and I'm very pleased (if I do say so myself) with the way it quilted.