Anthony,
This is more a FYI article, I would say. Just that you aware which issues are fixed already.
Rollups are basically a collection of Pointfixes. And Pontfix is a code change created to resolve particular issues of particular solution.
Latest rollup v4 contains all previous rollups (1, 2, 3).
But! (there is always but, isnt`it?)
Rollups don`t go through full suite testing as Service Packs do. Only solution based testing performed.
So, taking into consideration above, I would say that you need to install the rollup, which includes the hotfix for issue you currently observe.
Meaning, if you have issue documented in rollup v2, you better install rollup v2.
If you have two issues from rollup v2 and v3, you should go with v3 as it will contain pointfixes for both.
However, there could be some unwanted issues introduced with rollup v3 (again no full suite tests are done)...and in that scenario you should definitely go with version4....
This might sound too complicated, that is why I suggest, you need to contact Symantec support. Symantec Tech Support should have latest information on rollups and advise you the best approach.
And as all rollups are distributed via Tech support only, you will end up with them anyway.