It's very easy to get started with, it has all of our needs covered including reporting that can be linked up perfectly from Salesforce! The platform seems robust enough should we need more power in future but this isn't something I would worry about now as they are working hard at adding new features every month or so - which helps keep me happy :) We don’t have too much customisation needed because everything works out-of box without us having any knowledge required (which makes life easier!).
However if you want some extra bells & whistles then there will always come an option down your list somewhere else though :). If its hosted internally within sales force than no issues using their integration toolkits however where ever possible prefer 3rd party solutions like Datalink when dealing externally especially those who do not know how SFDC flows work etc..