The Axis and the Vegas roll down the same assembly line. All the mechanicals are the same. The fiberglass shell is a few shades different in color, and the fabrics and wall covering are a bit different. The headlights are in a different configuration.
If you can, rent a unit with a floorplan similar to the one you want. Now with
www.RVshare, you might be able to rent the exact one.
You didn't say if you will be traveling with kids and/or pets, which could influence your choice. For the two of us and the way we travel today, the Vegas fits us just right. Happy Hunting!