I've had absolutely no problem using it. If you prepare your fondant/gumpaste correctly it cuts perfectly. If people are having problems they are using the wrogn medium or not preparing it properly. There is a learning curve.
Try contacting Debbie at icingimages and she may be able to help you. She's very good with canon printers and will help even if you didn't buy from her, however I highly recommend her gold label inks and premium icing sheets.