You want to check three things for outdrive oil, given you are below the oci recommended hours and know that the right oil is in there. For my VP DPS oci is 100 hrs.
1. Check for water. let out a tablespoon or so from ther bottom plug. If there is any water or milky oil, you will have to rebuild.
2. Check for dirty black oil, excessive metal shavings or burnt smell. regardless of hours, bad drive oil should be changed.
3. If all ok, check level.
If those are ok run until recommended oci is reached. Use recommended oil and watch oci's. Since there is no combustion bi products in there you don't have to worry about leaving used oil in the drive like you would in an engine.