I just looked at the specs and downloaded the owner's manual. It looks like it does NOT have a needle down feature. That would be a turnoff for me. I have two vintage machines that don't have needle down, and though they do a great job at FMQ, I find that I really enjoy having that feature on my main quilter, the PQ1500s.
I'm not sure what advantage the Jazz would have over the PQ1500s, or the similar machines made by Juki and Janome. It does have an extra 3" to the right of the needle, but it doesn't look like it has as much vertical height, so it may be a wash in terms of actual quilting room.
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