Don't know a thing about the Juki, but I LOVE my 6600 ... and don't even consider the 6500, the 6600 has a lot more to offer and for only a little more $.
I've heard good things about the 7700 but unless you HAVE to have a freearm, you'll be VERY happy with the 6600. Ive sewn denim quilts, outdoor cushions, boat bags etc w never a problem. If you have a cabinet or custom table, be aware the 7700 is a larger machine, and won't fit in most.
Last edited by TexasGurl; 06-14-2012 at 10:37 AM.