What do you like best?
And, yes... Jboss/wildfly should be default web server for java web applications. Is an open source Java EE application server implemented in pure Java, specifically the Java EE specification. Being Java-based, JBoss can be used on any operating system for which the Java virtual machine is available. WildFly is free and open source software, subject to the requirements of the GNU Lesser General Public License.
What do you dislike?
Wel, it is not perfect. All you can see es lines and lines of code, errors, warnings, information, all is text in a console. It need a configuration that is not for beginners, at least not alone beginners, without an expert helper. If yo need to apply styles, be patient, consult the web and go ahead with this arduous (and hard, if you use faces) task.
Recommendations to others considering the product
If you need to run web applications developed with java, do not hesitate and use jboss / wildfly, the initial configuration is puco ruda at the beginning then you get used to it and finally it is routine. It does not need servers of great magnitude and you can always count on your console to control your log. Besides, it has its web interface, where you can configure many things, like datasource, drivers, deploys, etc. IT'S FREE.
What business problems are you solving with the product? What benefits have you realized?
Five years ago, when i start to development in java web applications i needed ans erver that can run those, and find jboos. This along with the help of communities on the web, allowed my applications to come to life and be used by my clients.