Hello
Everything is said in the note you have read (1803986 - Rules to use SUM or SPAM/SAINT to apply SPs for ABAP stacks).
For ABAP stack you can use either SUM or SPAM, SUM offers few advantages
- shows the point-of-no-return with reset option that can withdraw all changes
- can also upgrade the kernel
- allows to reduce downtime if you are applying a lot of SP
SPAM is simpler and, as doing less check, is by the end faster.
The number of SP to apply is important enough for recommending SUM especially if downtime is an issue.
For the Java stack you won't have the choice as stated in note 1589311 - Replacements of outdated tools via SL Toolset
you must use SUM for all NetWeaver versions from 7.0 and higher.
Important remark: you cannot only apply Basis SP only, SP should be applied for all the components (Basis, Abap, Appl...)
Best regards