I've used Ashlar products for many years now. They have always been known for their intuitive interface. Unfortunately they have also been unstable and slow to upgrade. Xenon is easy to use for simple modeling. It is also easy to generate nice limited subject renderings. However I have always been challenged with creating more complex geometries. The ACIS based model is not friendly to the Nurbs surfacing and protyping world I interface with. The modeling does not do well with larger scenes. The shadows quickly become aliased (jaggy). I will not be renewing my license. There are too many other programs that appear to offer greater capabilities and value.
Xenon offers very high design flexibility at a competitive price. The history tree allows for easy changes to the design at virtually any stage of completion. The rendering capabilities are good allowing for top quality presentation images to be made within the package. It features a wide array of import and export functions to provide compatibility with other CAD software. A wide array of 2D sheet tools are provided. Prints, however are this programs weakness. While it excells in the 3D world, its 2D prints could use some improvement. They are functional, but not as good as some of the other packages on the market.
Overall it is a very good package, and for 3D modeling, design exploration, plus moving to production in 3D it is excellent.