Want to buy a new rig but afraid of quality control issues

The key to buying a new RV is doing a thorough PDI.
That means curbing your enthusiasm and check out the entire thing. Get on the roof, go underneath. Check screws, seams, caulk joints, doors, drawers switches, latches check it all. Allow time and don't rush. A few hours going over the rig will save a lot of headache down the road. If buying out of state. Camp close by and give it a shakedown before leaving the area.
There is no need to fear a new unit as long as you are willing to make the effort to check it out.