We purchased our 2012 Bay Star 3302 in 2018 and I've found it to be a very well built rig. As with any motorhome built on the F53 chassis, aftermarket improvements can help with handling. Our rig already had Sumo Springs. Handling improved after getting new tires, front end alignment and adjusting air pressure in tires based on axle weights. A Roadmaster steering stabilizer improved steering performance.
The coach is well insulated and the double pane windows are a nice feature. We're very comfortable even in cold temps in the teens. Two AC units provide plenty of cooling even in very hot summer weather. Using the propane furnace keeps the water tank/bay from freezing but I monitor it with remote temperature sensors.
Installing a 5 Star Tune really improved the transmission shifting points and I recommend using the tow haul mode which makes it easy to downshift the transmission and avoid excessive braking.
There's no question that diesel pushers have some advantages, but the Newmar Bay Star is a high quality product that can be a viable alternative depending on what you need or want to spend for a motor home.