I can also recommend the Janome 6600Mp, but personally own a sort of cousin of it, the Elna 7300.
http://www.elnausa.com/en-us/model_quilt_elna-7300.php
I cannot say enough how much I love this machine. I got it for less than the 6600 typically goes for, and I find the controls easier to work with. Generous harp space and its Integrated Adjustable Feed (Janome calls its famed AcuFeed) make quilting SO much more enjoyable. One difficulty is that Elna dealers can be a little thin on the ground in the US so you may need to order online. I actually acquired mine new from eBay for under $1100... risky I know, but I asked the seller three million questions and got a good vibe about him and the auction, and my warranty is valid. Under these circumstances, I was not able to take a class, but frankly, I haven't needed one.
I am sorry because this website is half Bernina-ville
, but I just have not found that Berninas are worth their cost. I was just sewing on a brand new 440QE at the Quilt Festival in Cincinnati... cramped harp space, no automatic threadcutter, and available for $2400. I almost fainted, then came home and kissed my Elna LOL!
If you are more curious about the Janome 6500 or 6600 (or even the new 7700/Horizon), there are Yahoo Groups for these machines that can tell you all about them. Though I do not own one, I find them informative for maintenace tips and various how-tos's that translate well to my Elna 7300.
I know a number of Viking/Husqvarna and Pfaff owners who are very happy, and Babylock is another name that crops up, but the first two seem also to get mixed reviews. The most satisfied machine owners seem to have either Berninas or Janomes. (Believe, I did a LOT of research as I was saving my money LOL.)
In any event, this is a fun process... enjoy and I hope you find the perfect machine for you!