They both allow you to get service subscriptions only for the systems on which you want support, rather than requiring service for every system in your enterprise.
There are two offerings available as of March 2019: 5737-F-J49. IBM recommends running with a current update of Java 11.
It is always suggested using the current update of a Long Term Support (LTS) version of Java. As stated above, IBM i Access Client Solutions (IBM i ACS) 1.1.8.0 released in June 2018, IBM i ACS is supported on Java 8 or higher.
