Newer firmware usually contains bug fixes along with updated and tweaked write strategies for some media. The updated firmware will usually also contain write strategies for new media sometimes new features are implemented.
In isolated cases there are adverse effects in using the newer firmware but often you can revert to the old firmware. Not so in your case because the firmware shipped with your drive is not available elsewhere.
This is a user's choice, but whenever there a recall on my automobile I usually take advantage even though I might not be personally affected.