E.A.
I've never owned a Dyson but I do have a Rainbow that is over 20 years old and still works like it's brand new. The only thing I have replaced is the bare floor brush attachment b/c the brush part finally fell apart. I don't deal with filters or dust when I vacuum, b/c it all goes into water. To empty the water tank, you pour out the water into the toilet through the spout where the hose attaches (after removing the hose of course) which leaves solid matter that is easily dumped onto the garbage. We have a cat, and have owned cats for 5 years and have no problem getting the cat hair out of the rugs (we have area rugs over hardwood floors).
The one thing you have to account for with a Rainbow is that you HAVE TO empty the tank EVERY TIME or it will start to smell and get moldy. You can't leave it for the next day.