To mitigate the problem with the different owners you can create a generic suitelet and create as many deployments as you need for different owners and then call each corresponding suitelet from a Map Reduce...

@alien4u Thanks for the ideas. NetSuite support told me that both N/record and N/search modules are unable to do the last step - i.e. the changing of owner from old owner to new owner.

I don't think that is correct or entirely accurate, you can create and save Searches, you can load and add filters or columns... you may not be able to change the owner but searches are scriptable.

Agree with @alien4u. However, if you are looking for ancillary stuff like Highlighting, or various other aspects of search that aren’t readily available in script, you’ll be missing out on all of that (email alerts, etc)