Ken,
I had considered those, but I was afraid they might be sensitive to grain direction (start a split if the grain is in line) and only work in really hard wood. Can you shed a little light on how well they work? Is it rare (or never) that you decide it won't work for the aforementioned reasons? How much do you part off?
If nothing else, it should be a good way to make hardwood faceplates.
With my previous lathe, years ago, I bought a few 1"x8TPI nuts at Lowes for about $1 each, traced their outlines onto scrap and cut holes for the bolts on the scrollsaw. They didn't fit perfectly, which was actually part of the plan - I put epoxy in the gaps around them and they were rock solid. The plates had to be surfaced on the lathe, but then they were fine. I might make a few more of those now that I have a decent lathe. Using faceplates is not as much of a pain when you have a few (but I may still have to talk to Santa about that $100 Grizzly chuck).