We've only had our KZ (Spree Escape E204S) for a year (4,500 miles) and it's held up pretty well. We've had two issues fixed under warranty and once we documented the issues KZ took care of them.
One of them was a broken bath tub drain pipe connection. I'm still alittle baffled by how it might have broken (occurred on a trip from NY to FL) other thant the fixture might have had a crack in it when it was installed and during the bumps and vibration during travel ultimately failed. We ended up with gallons of water trapped in the underbelly saturating the under floor insulation. We were about six days into a ten day trip when I noticed water dripping from a hole in the underbelly where a pipe passes through it. I think noticed that the underbelly was bulged and when I got under the trailer and pressed on the budge I could tell it was holding water. I punctured the underbelly covering with a knife and over a few hours period out came a few quarts of water. I figured out the water was coming from the shower, it wasn't massive amounts of water at any one time and I knew it wasn't going to be a quick repair since the water was going to have to be complete drained, insulation removed and trailer left to dry out before replacing the insulation and resealing the underbelly.
Once we got home KZ arrange to replace the broken drain pipe, remove and replace the damaged insulation and reseal the underbelly.
The other issue we had was shorted running lights. It turns out a screw was inserted right next to a portion of the running light wiring and again, via bumps and vibration while traveling, the screw worked its way through the wire insulation and shorted the lights blowing the trailer light fuse in my truck. The dealer found the short, repaired and relocated the wire, and the fuse was replaced.
These weren't really complexed issues to fix and beyond them the trailer has held up well. For the money we think we have gotten good value. Based on what I've read on other brand specific forums there is the potential for issues with all of them and the warranty is there to deal with them at the manufacturers expense.