ADB is more suitable for instances where you have a lot of processing
ADB is more suitable for instances where you WANT that a particular action on a DB Table triggers a BW process.
ADB adapter is best for publishing from database.
For simple inserts and UPDATES then ADB subscriber is best.
In case of insert or update to database then check if you have complex JDBC inserts, transaction management and other dynamic queries then JDBC activities are best.
JDBC is more suitable for running dynamic code where in runtime you can execute statements with different values depending on process execution.