I love my 6600!! hands down. I have tried all kinds. Singers are not what they use to be, since moving to Japan (no offense). I had a Viking, loved it. Berninia did not like, Pfaff I liked, another Viking I really like and use for embroidery. And I do my piecing with my 6600. I love the accufeed feature! It is great for quilting and putting binding on. Most of my quilting is on the longarm, but small things get done on the 6600. It is a work horse. AND you cant beat the cost!!!! I think the others are just way over priced. so, I say go for it. A good dealer makes a difference, sounds like you will have one.

I have no experience with the 6600, but I have had a Janome 4000 for many years and I love it. I have quilted many, many quilts on it and it always does the job. So, I can only assume that they have improved on it with the 6600.

I don't have the 6600P but I have had Janome machines for the last 20 years - at present, the Horizon and the 11000 - and wouldn't buy any other make. I did stray one time but immediately regretted it! Having said that, I think all machines have their own idiosyncrasies, and you get to know them with use.

I have the 6600 and love it. Bought it last year, I'm very happy with it. Love the speed control, AccuFeed, thread cutter etc Sews more smoothly than my last Pfaff did. Previously owned 2 Pfaffs, 2 Vikings and a Kenmore (Janome) years ago.
Decided on the 6600 after so many good reviews, and getting great feedback from quilters I know. I know at least 15-20 quilters who have it and love it. My SIL & niece both have one now and love it. It's a heavy duty machine, made to last. IMO Janome gives you a lot for your $$$. Go take a test drive ! :)

Love mine.

If you do a SEARCH (above) for Janome 6600, you will see even more responses to your question.
I would say most of us that have it are quite pleased.

Awesome

I love, love, love my Janome Memory Craft 6600. It does everything but talk to me, and sometimes I think it even does that. I can not say enough good things about it. You will be thrilled to have it.

I just brought a Janome Horizon 7700 and love it. I have owned 3 Janomes . Jem Gold traded it for a DC 2010 which I still have,and now 7700. It is not that hard to a machine to operate and haven't tried FMQ. Only had it 2 weeks :) I have heard good things about the 6600 Take a class before you buy it if the dealer is okay with that. My dealer let me come and play on it before I made a commintment.
Good Luck

I have to say that Janome and Bernina owners are usually happy with their purchases. I got my 6600 used, I already had a Bernina Activa which is sort of the low end for Bernina. I knew I could never afford a high end Bernina ($10,000)so at first I felt like I was sort of settling for a Janome, but at $800 I thought I could always get my money back if I hated it. Well I love this machine, it is a workhorse. I not only quilt but also sew clothes. The features I wanted most were the even feed and the thread cutter. I find I don't use the thread cutter as much as I thought, but there are plenty of other features that I have come to rely on. I don't use any of the decorative stitches other than when I played with them when I first got the machine and to label my sons clothes.
Check out the Yahhoo 6500/6600 group, it was a great resource for me when I first got my machine.

I v'e had mine for nearly a year and love it. I'm still discovering new things about it. I've done little FMQ but that's one one my future aspirations. It works great for SID. I shopped around and "test drove" a lot of machines before buying this one. I have always had Kenmores.