The trick is an electric soft roller head with two rollers that can rotate 360 degrees around the absorber.  It makes it very easy to guide furniture, pets, carpets, and into hard-to-reach corners.  It's a new look for Dyson, and the company seems to have done it.  You can lay the vacuum flat, parallel to the floor, and then place the roller under the sofa and other furniture, which takes more effort on other machines or even Dyson's own vacuum cleaner.  It's a pleasure to use.  This accessory really completes the machine and uses mechanical efficiency to make up for the lack of original power.  Useful?  It is suitable for hard floors where there is usually dust and fine debris.  However, with a little more difficulty, the suction might be insufficient.  Cat litter?  Be prepared to experience it over and over again, but still keep it.