I have the Brother PQ1500S and I love it! I've had it a couple years and have pieced 5 quilts and quilted 3 on it. It has excellent speed control, so you can go slow enough to do one stitch at a time or really fast. It's mechanical, not computerized. Just a machine-machine, so if something is off, you can figure out what it is.
I can't compare to the Juki, which I've never used or seen.