Most of the time I love my 6600, it's just when the bobbin acts up, it's very frustrating. And I do use only Janome bobbins and good quality thread. I can't say that I was ever super thrilled with my AQS but it's nice and light for class which is what I bought it for. I would probably still consider the 6600 if I was buying a new quilting machine. After all, I think pretty much any machine has some complaints about it.