I used the Superior Metallics on a smaller project (comfort quilt), using my Bernina 820 and not on a long arm. I found it very easy to work with, but I used it as a top thread only.
Back a couple decades ago the metallic threads were pretty horrible... thick, broke often, scratchy, and were better used as bobbin threads -- thicker fancy threads can often be used in the bobbin as they have less distance and turns in the pathing.
Not a very good picture but here's that project attached below.