My experience based off reviewing both.
WordPress out of the box has better: administration pages, pretty URL's, and a significantly higher number of themes (free and paid).
Wordpress requires a database, customization requires PHP development (either for theme changes or plug-ins).
BE.NET with the .Net architecture is easier to customize with controls, extensions, and widgets using ASP.NET. BE.NET can run without a database, but can also run with a database. Running without a database and a .Net based architecture was what
led me to utilize BE.NET. I've deployed about six sites on BE.NET. Performance has been excellent.
If your looking for a solution out of the Box, WordPress is more widely adopted, easier to find a host that installs it out of the box. If it doesn't work out of the box, then it can be a pain to troubleshoot.
If your a .Net developer and looking for customization, then BE.NET would be the better solution (IMO) because of the .Net architecture and depth of additional controls / features.