I bought a Bernina 450 in January. LOVE IT! It does not come with the embroidery add on but I'm not a big embroidery fan anyway. I can always buy it later if I change my mind. I think that the 500 have a smaller stitch width, if that matters to you. I think the 500's have a 5mm width, while the 400's have a 9mm. It might be worth talking to the dealer about the specific differences. Good Luck!