We've only had our 2012 Newmar Bay Star for a few months, but one of the reasons we narrowed our search to Newmar, Tiffin and Winnebago/Itasca motorhomes was their quality. I don't know if I would say that Newmar is better than Winnebago. The answer may depend on what options are installed.
There are a few things I can say about our Bay Star. First of all, the wall construction makes for a very quiet interior i.e. outside sounds are pretty well muffled. Secondly, the double pane windows are a plus and will be appreciated when we are in colder weather. The cabinet work is first class. We were lucky to find a unit with the 7500 watt Onan generator and it's a joy to be able to run the generator and not worry about whether one or two ACs are running at the same time as the microwave.
That being said, I'm sure that we could have been very happy with a comparable Tiffen or Winnebago motorhome. Consider going to something in the 32-34' range as the shorter 29' and 30' motorhomes have a reputation for not handling as well as longer units. Do some research on the Jayco motorhomes....one of their shorter models has a poor reputation for driveability. I will say that Winnebago does a great job with the layout of their cabinets (kitchen and bedroom) and some models have more counter space than Newmar when you are looking at 29-34' motorhomes.
Finally, if looking for used, consider what modifications have been made to the chassis. Our Newmar had already been fitted with rear tracking bar and Summo springs. Once we replaced the tires and inflated properly and had the front end aligned, it rides pretty well on the highway and I don't have any issues with it being tiring to drive, unstable, etc.
Final point: Make sure you buy a motorhome with 2 AC units, especially with a motorhome that has a darker paint scheme. Our brown box really draws the heat and if I had a choice, I would rather have a white exterior with contrasting trim. Although we could probably squeak by with on AC unit, when it's hot, humid and sunny, we really need to run both AC units during the day. At night, we can usually turn off the rear AC unit and benefit from less AC noise.