Flexibility to create customizations as per requirement of my organization with ease is one thing which I like about this product most out of all other tools available till now.
The support team provided by them are very helpful when you face any problems during implementation or customization phase itself. Nothing much so far but it's just an initial impression after using few days only from their side. We have used XSLT capabilities within XIASoft ditacms toolkit alongwith C# code writing capability through VS2010 IDE.