I love my Horizon. I had the 6600 and hated it, it always dragged the fabric into the hole all the time and wasn't thrilled with the Acufeed on the 6600.
When I got the Horizon, I was thrilled that the fabric dragging into the hole wasn't happening, it's so quiet, I love the extra space and the lighting is awesome.
It is by far the best machine I own. I have the 11000SE from Janome as well, and I never use it now. The Horizon is just such a joy to use.