I actually don't have a preference. I usually just use the default locate implementation my distribution provides. I used mlocate before and when the distros switched to plocate, I rolled along with that without making efforts installing mlocate from a different source. Its the easiest and safest way to me. Usage and performance between mlocate and plocate seems to be identical in my experience (no benchmark, just how it "felt"). plocate is actually mlocate with a few patches for edge cases, if I understand it right.

I have it currently uninstalled due to an issue:

However, recently I had some issues with the locate and KDEs baloo (baloo can do content indexing too but I set it to only filename indexing, so its similar to locate). Those tools may have killed my previous system SSD and on my new one I noticed they used up Gigabytes of RAM and seem to be stuck. After investigating both tools seem to have choked on few filenames that contain unusual characters. Therefore I have disabled them for now until figured out how to deal with this (probably renaming) and try later again.