Stitch Samples
Okay, here's a little picture of some stitch samples done with the circular foot. Keep in mind that these are really quick-and-dirty samples done on broadcloth with no stabilizer (which really should be used for this type of stitching).
The foot worked great with the Featherweight 75; no problems at all. It did not work at all with the Quantum L-500. I'm thinking it might be (as someone else suggested) a problem due to the wider feed dogs. Even though the feed dogs are lowered to use this foot, and I adjusted the needle pressure to its maximum (as the foot instructions say to do), it totally pulled off-course on the Quantum. I wasn't getting round stitches, just lots of stitches bunched up on top of each other.
There are lots of adjustments you can do with the foot, and it comes with instructions to describe all of them. If you have any questions you need answered in the meantime, just ask and I'll be happy to answer.