Dyson vacuums are pretty good as a whole. I had one of their upright vacuum cleaners for a good few years but I killed it dead. I just do that with everything I touch eventually. So I hit Amazon and bought a Numatic Henry. Five star reviews galore but it's hopeless. No suck at all, falls to bits all the time, when you pull it around the centre of gravity is so high it ends up on its side and upside down every two minutes, and finally the hose holder is so flimsy it just pulls the whole thing over. The only solution for the suck is to run it bagless and then carefully dump it's insides into the bin without losing them everywhere which is damn hard. I actually want to take it outside and beat it with a cricket bat every time I use it.
But, screw paying Dyson prices. I'll get a couple off eBay/gumtree and fix them next time. Takes about 30 mins to strip one to parts and clean it as they are designed to be repaired. I do this with test gear so why not household appliances.
As for the hair dryer, Bosch do nice hair dryers for less than 1/8 of the cost. There are no nice vacuum cleaners for 1/8 the cost of a Dyson. Ergo, I don't see the cost justification for this hairdryer.