I don't own one but I teach new Deco owners about their machines at my dealership. I really like it. You have the ability to bring up designs, easily edit (rotate, move, rescale about 10 - 15%), add lettering and go! Saving designs is easy. Some neat monograms to quickly personalize gift items.
Having the USB port is REALLY nice. No cards to format. You can purchase additional designs in multiformat cd or stick (deco reads .exp) and transfer to a Bernina usb stick.
The only thing that DD might really enjoy (now or down the road) is Explorations software. Even the basic level has 40 additional fonts and you can edit design more quickly and see them in color on your computer screen. It's about $300 and is a great way to jump into embroidery without breaking the bank.
Hope this helps.
kim