I have the Janome 7700, it has an 11" harp. I also have a Brother 1500 with 9" harp, and a Juki HZL-400 that has approximately 7" harp. I have to say for me the Juki is the most consistent and does the best job of quilting and 1/4" piecing. If the Juki had an 11-12" harp it would be my dream machine! Even though the Janome has the accufeed foot, the Juki does a better job.
Of course this is only my opinion. I always say if we all liked the same things how dull this world would be..
K