Metron uses Storm, Kafka, HDFS, Spark, Zepplein, Zookeeper and HBase primarily, which are available in other distributions. However, the primary deployment method is through Ambari, so it tends to work a lot better on HDP. All Hortonworks testing of the platform is certainly done on the HDP platform, so it will certainly be a lot easier to use. For AWS type deployments, it may also be worth considering HDC, which is essentially HDP but packaged up in the same way as EMR running on Amazon. s3 could also make sense as a long term storage platform for Metron replacing the HDFS default.