The ease of use, user interface, customization options are excellent! We have been able to set up our lab in such way that it has become very efficient with minimal staff training required.
It does not integrate well into other applications like Excel or Access so you cannot pull data from your SQL server directly through LIMs - this can be solved by using ODBC but then we lose some features like custom fields. When I first started working at my current job as Director/Owner there were only two people who knew how to work LIMS systems. Nowadays everyone knows what they need to do within minutes once given instructions via email which makes support much easier than before when all knowledge was passed down verbally over many years.