I have the 6600 and the new Horizon. I'm very blessed! I love them both and never had a bit of trouble with the 6600. I was going to trade it in on the Horizon, but changed my mind, because I was just attached to it. The Horizon is lovely because it also has a free arm--and that was my only complaint about the 6600. I've heard that the few features that the 6600 has over the 6500 make it a great machine. I honestly think that you would love any of them. I've been sewing on Janomes for 25 years now and love them all.