We have sold Airstreams for 37 years both Motorhomes and Trailers. ALL sorts of problems.
Something like 70 percent of all Airstreams made since the mid 1930's are still on the road. Compare that to many standard box trailers that barely last the loan, if that long!!! Quality is often how long a product lasts not that it might need some maintenance along the way or fix a latch or microwave here and there. And if you sold Airstreams for 37 years the quality must not have been that bad or you would have dropped them a long time ago. The very fact that you sold them for almost four decades tells me they are a product worth selling and buyers are getting something of 'quality'.