Apache Committers can get a license for IntelliJ IDEA Ultimate without engaging in e-mail conversations, in a matter of minutes, by using their @ apache.org e-mail: https://www.jetbrains.com/shop/eform/apache?product=ALL. There is at least one little reason to use Ultimate for Druid development: the "Detecting Duplicates" feature which is available only in Ultimate (see https://www.jetbrains.com/idea/features/editions_comparison_matrix.html).
People who are not committers can also apply for an Ultimate license for Druid development here: https://www.jetbrains.com/shop/eform/opensource?product=ALL.
