Another vote for Brother PQ1500S machine. It has a 9" throat and will sew at a very high rate of speed. I have it on my home made quilt frame (10') and it does a wonderful job. I am still in the learning curve with it as far as machine quilting but I do like it for what I am using it for. This machine was highly affordable and appears to be very well built. No frills with this machine, just a heavy duty sewing machine, it does have an automatic thread cutter and needle up and down control. I did add the Grace speed controller to it so that it would be more convenient to use it on my frame carriage. Before I mounted it on the frame I did piece several quilts with it just sitting on my sewing room counter and it was wonderful. So either for piecing or using it for machine quilting I feel it is a winner. Good luck finding a machine that you love!

The last email ad I received from Allbrands had the Brother for $569 with free shipping. :-)

Wonderful machine. Use mine daily.

I love my Sapphire; but haven't used it on a frame...

I have a Brother 1500s and a Janome 1600, basically the same machine with 9" harps. I had the Janome on a frame and used the Brother as my "daily driver" for piecing. I purchased both machines used for $400 each. If you want used (or "pre-loved") machines, don't stop at checking with your local dealers. Put the word out amongst all your friends (including the non-quilting ones), your local quilt shops, and your guild that you're in the market for a good, used machine.

I strongly, strongly recommend you get the largest throat that your frame and budget will allow. I ended up being very disappointed with the 9" harp, because once you get the quilt partially quilted and rolled up in that harp, you end up with only maybe 3" or 4" of quilting space.

I looked at a Brother INNOV-IS VQ3000 Dreamweaver today. It has an 11.25 throat and is 5 inches high under the arm. I will sew over 1000 stitches per minute, is laser guided. It can even thread it's own needle. Has more bell and whistles than I can even imagine using and all for less than $4000. Well if I am going to dream I should dream big.

Brother PQ1500S
Juki 2010
Babylock Jane
Janome 1600P

I have a Baby Lock Jane on my frame and do not like it. 9 in is just to small to really do anything.
So it sits until I can afford at least a 18 in throat.
These machines are not made for long arm tables so threading is a hassle, I have to move it all the way to the end of the frame to thread it. You cant bring the bobbin thread up cause you are no where near the needle. Bobbin thread running out is also a problem and it runs out fast and you dont know when it will run out.
I even have a stitch regulator on mine which I love.
Just learning to use a frame is a big learning curve so with a small machine it is just not worth the hassle.

I agree with the statement that 9" is too small, but there are a few things you can do to make quilting with those machines less problematic:

If you switch to Bottom Line bobbin thread, your bobbin will last a lot longer. Because Bottom Line is finer, I can get a lot more thread on the bobbin.
My machine has a needle up/down button, so I am able to bring the bobbin thread up. This might be something to put on your list of things you HAVE to have.

Don't know the Babylock Jane but I have the Juki 98QE & it is a workhorse. No bells & whistles but a very hardworking, sturdy machine with a 9" throat.