I would highly recommend the Janome 6500P. It has a 9 inch throat, is a real workhorse and has plenty of bells and whistles such as thread cutter, needle up/down, plenty of decorative stitches. The 6600P is the next model up and they will tell you the dual feet is the greatest thing since sliced bread, however, I don't care for it. I find it takes less time to put a walking foot on than to deal with how cumbersome it is to use their dual feed. Not as user friendly as the Pfaff or Babylock dual feed.
Anyway, you can buy a new one for around $1000 and find used ones for around $600. Hope this helps.