I doubt that it's the machine's fault that it dances. Even my Bernina 440 danced around when I put it on a Costco table. It's fine in the recessed cabinet I purchased for it. Having a mat under the machine also helps.
I second the Costco table issue. I had to place my Viking Sapphire at the very end and even then it wasn't perfectly steady. I solved the problem with a $20 table from a thrift store.