Thor has made steady improvements on the 29h for the past 3 years. My 29h is a 2015, and did have it's "issues" that had to be sorted out. Luckily I bought from a dealer who had some "good" techs. that were able to fix all the problems.
Most all problems were "electrical" related issues.
Transfer Switch burned out. (Warranty)
Leveling System not wired correctly. (Warranty)
Leveling system shorted out due in part to bad solenoid (below) (Extended Warranty)
Bad Solenoid (Emergency Battery Start) (Extended Warranty)
Hot Water tank wires not routed properly causing them to short out. (Warranty)
Slide Out not synchronized. (Warranty)
Battery bad in engine bay (replaced under warranty)
Batteries went bad in the coach, due to Bad Solenoid (above) which didn't allow proper charging. (My Cost)
Other items:
Had to replace front tires in less then 15,000 miles, ( Needed alinement, which Thor does not do at factory) (My cost)
Sidewall blowout on right side rear dual tires (Had to replace both tires) I learned later that Michelin had recalled those tires, but I never heard about it.
(Tires Replaced under Tire Hazard Warranty)
That's about it, except for cabinet, drawer, and door adjustments. (Warranty)
I strongly encourage that you purchase an Extended Warranty, The leveling system alone was a $3000.00 repair. I just had them add it into the financing.