I've had a DC03 Clear, DC07 Standard and now a DC14 Allergy. The first thing to mention is Dysons do go wrong, but where they are different is that the Dyson customer service is excellent, the telephone number is printed on the machine - and one call generally solves the problem either by getting spare parts sent out or collect/return repair.
It is one item it could be worth getting extended warranty, because if it is under warranty , it will be repaired by Dyson.
Tips: avoid the clear plastic models , the plastic is much more brittle, I had several replacement handle/wands/sole plates under the 2 year warranty with my DC03 Clear. The DC07 has a lot fiddly bits which can break - the foot plate cover, the internal hose can split due to wear/n/tear, the valve pipe clips can break, but it is a powerful vacuum.
The advantage is that Dysons are built to have parts replaced as they wear out, sort of modular design, it is not often they are beyond repair and many spares are also available on well known auction site/ Dyson Website either new or secondhand. Secondhand one's have a good resale value if you decide to upgrade.
My Dyson DC14 is too new , but so far it seems the best model so far, great suction, better design. I've kept the DC07 for cleaning up after DIY.