We have a KZ Durango - it's only a year old, and we've had our share of things that needed fixed because they were built cheaply; but no more or less than our previous camper, a Keystone, and no more or less than our parent's have had to fix in their Keystone.
KZ has been in business for 40 years, and has been a winner of some quality award for quite a number of years. We were more familiar/comfortable with Keystone because everyone we know has a Keystone brand (we camp with many other families & friends - all own Montanas or Outbacks, both by Keystone) but we ultimately fell in love with our floor plan, and have seen nothing comparable to it in any other brand.
We have not been disappointed, but again, it's only been 1 camping season so far.