I use to use them in my Viking Designer SE just when it was set up to embroider - really made a difference! Then I tried them for all sewing in both my machines and I do feel there is a definite difference in the stitch quality especially when FMQing. I believe the quilting diva Sharon Schamber also uses the Genies. These may be just a specialty type of washer that might can be had via a local plumbing store (I'd heard this on another group but have not checked it out).