I would look more at layout and weight than brand. They all use pretty much the exact same components. With the exception of an Airstream there really isn't a big quality difference between them. You'll know when looking at them. Most manufacturers have low, medium, and higher end material lines...i.e. Full molded front cap, laminated vacuum walls vs lap siding, aluminum wheels vs steel etc.
The technology in these at the price point is impressive. Literally a house on wheels, but at the same time you'll be surprised at how cheaply assembled they are. But they work, and work really well all things considered. Like the old phone answering machines, they all do the same thing. You'll be camping with any of them making memories with your loved ones. Don't get too hung up on the buying process.
