I think the 6700 comes with more accessories and has a stronger motor. But the 6650 still has pop out plate, 9mm stitch width, variable needle positions, up/down needle, start-stop, wide 10" harp, mostly metal exterior, superior feed-system (vs accufeed on 6700) and more than enough decorative stitches. What is the going price for the 6650? If under $2000, that'd be a great deal. I kind of wonder if they might strip it down further and offer a budget model and if so, that would be my preference ..sometimes simple is better.