Dahua is extremely reliable brand, reports of any dahua failure on these forums is extremely rare.. and when they do they are usually self inflicted, ie, not properly waterproofing the connections, or screwing up a firmware update.. but bricking from firmware update is much less frequent of an occurrence than Hikvision or anyone else.. they do try to prevent you from bricking it, but shit still can happen.
If you were to buy these cameras from a US Distributer offering a warranty, you'd be paying so much more you could proabibly import a spare camera from China to use as backup and still end up spending less money.
I'm fully confident we wont have another MiniHuisun or Longse fiasco with these cameras, Dahua makes cameras for FLIR/Lorex, Swann, AmCrest, GeoVision and many others.. and they dont just make cheap shit, a Dahua employee was just showing off a $90k Thermal/Visible Combo PTZ here earlier this week... Check out this post:
SD6AL230F-HNI laser light performance