It's easy to use, fast (I have not encountered any problems so far), it is well documented with plenty of tutorials online for beginners as me; I am using this database system in my master thesis about statistical analysis methods used by insurance companies - hence its importance! However there are some features that could be improved such us automatic backups or better documentation regarding how data can get corrupted/lost when doing an import from another DBMS into monedb like Oracle has done through flashback tables etc..
But overall very good software if you need something really simple but reliable at low cost compared other databases outthere!!