I have a V11
So far, I have had to replace the trigger (broken plastic inside), replace the filter unit, replace the main wand unit (cracking plastic at joints). I will soon have to replace the main housing, as it is also cracking.
We are far from abusive. It performs great, but the plastic simply does not hold up.
I would not plan on a Dyson lasting more than 5 years, best case. And be prepared to do some maintenance on it.