We've had this for around 2 years now I thought I would set out our views as seasoned users.

This is a good product and was our first Dyson. Whilst significantly more expensive than many alternatives overall it has been worth the money.

The main ball function slides effortlessly around out flat, and has optional brushes (simple press of a button) for switching between carpets/wooden floors.

Suction is effective on both wooden floors and carpets. I've cleaned the filter a few times, which seems to improve performance if it starts to lag - just wash the filter in cold water. The main section also comes apart easily and can be washed.

It's easy to empty the transparent cylinder. A press of a button and it detaches from the main appliance - just the press of a further button and the cylinder bottom drops out and the contents fall into the bin. No messing with bags etc. The fact that the cylinder is transparent helps to see if it is full and also means you can keep an eye out for things which ought not to be in there - such as when my wife vacuums up bits of our kids' lego and other toys!

The detachable hose for getting to hard to reach places/cars etc is a little flimsy and we've had to purchase one replacement, out of warranty - about £20 but very easy to order from Dyson. It is good for getting to hard to reach places. as intended but the 3 default tools/attachment aren't that great and keep falling off. I understand there is a more advanced tools package which may be worth looking into if you use this part of the cleaner more often.

As to the allergy benefits, I am a hayfever sufferer - allergic to house dust etc. I have noticed that over the last few years my suffering seems to have diminished somewhat whilst at home but I have no idea if this relates to this product.

In response to a helpful comment on the original review, I should just add that the noise levels aren't unusually high. One important point is that we do live in a flat and it is quite a heavy piece of kit so may not be ideal to be lugging up and down stairs on a regular basis, although the same applies in my experience to any reasonably powerful upright vacuum cleaner - the suction power does come at a cost in terms of weight. However, the ball design means that moving it around on the same level is pretty effortless.