We also have the DYSON and it is worth it with my 4 kids 2 dogs 3 cats and a DH that likes to use it on the furnace it has never lost any power and i have only cleaned the filter once in 4 years!!
I've had a Dyson. it lasted 5 years. I lived in the desert, and had Malamutes at the time. It did reasonably well all things considered, but I won't buy another. We bought a Meile canister vac this last time. It wasn't cheap, but it's also running circles around our old Dyson pet. I got turned on to them after reading an article from a guy who is a vacuum repairman by trade. Did some more online research and learned about how basically indestructible these pigs are, and decided that was the one.
I am also, as my husband calls it hard on vacuums. I do expect my vacuum to pick up small things off the floor like wood shavings, small candy wrappers, and hair. Mine and our 4 dogs. Unfortunately I'm to cheap for a Dyson and settled for a shark. It will suck the carpet off the floor. Im overall happy with it. 1 filter, no bag, plenty of attachments, easy to empty and take apart, plus it has a detachable canister so you can move it around.