My machine collection isn't huge. But my favorite that I've ever sewn on is the Singer 201-2, hands down. I love how it purrs while it stitches away. I like the Singer 15-91 and it's really reliable, but it's like driving a tractor after the Rolls Royce 201-2! I still need to get the hang of treadling, but I hope to soon when I set up my treadle.