I like how easy it was for me as an outsider with little experience in Scala or Spark Streaming API's etc.,to start building my first realtime system using these tools/frameworks! The documentation could be more comprehensive when you're getting started but once your familiar enough wtih what each of them do they really help out alot!! We were able create our own live metrics dashboard which helps us monitor all aspects related to traffic flow within one single interface so we can easily see any issues at hand before things get too far off track if needed.