Our's has been a great coach, with super support from Tiffin on a couple minor issues.
I think the trips to the plant are similar to any other mfg, and is due to the lack of support knowledge, parts availability, and convenience. It is the same issue that all manufacturers have. When you have bought any mfg 100K+ coach, you don't want to take it to some local camping world that has people who really don't know what they are doing with your particular brand/model. If anything is broke, they undoubtedly have to order parts from the plant, assuming they know how to fix it. Your coach sits and is delayed.
For any brand if you drive to the plant you have the best skilled resources that know your model, they have immediate access to parts, and can get everything fixed up at once. Many who travel around just route themselves through whatever city is the plant every couple of years.
If you are handy and can do minor fixes yourself, the time between visits can be long.
DaveB, Raleigh, NC
2015 Tiffin RED 33AA
2014 Honda CRV