I have a 2013 Thor and recently looked at the current version of the same model. Most of the design/hardware issues that I have had have been improved on the current model. I was rather impressed. It is really hard to say about the labor but I really haven't had that many issues with things put together poorly. Even though their market share has increased since I bought mine I haven't seen as many complaints here as I did 5 years ago.
I was able to compare mine somewhat with very similar Forest River and Winnebago models and would agree that those were better built but they cost quite a bit more too. There were some things that I still like better about the Thor even ignoring the price.