I have the Tiara II, a sit-down mid arm and recently bought the Babylock TruGrip seen here:
https://babylock.com/accessories/sti...roduct_ID=BLTG
I saw it at a quilt show and the fact that it kept the stitch regulator close was the selling point for me. I haven't tried it yet, so hope it works as well as the demonstrator modeled. Often my SR will migrate too far away. I think I paid something like $69. so a bit pricey, but it may be worth it's wait in gold if it works.