Apparently, your experience with various indexing services has been different than mine. I found it is just too easy for the index to become 'out of sync' with

Apparently, your experience with various indexing services has been different than mine. I found it is just too easy for the index to become 'out of sync' with the actual file system and has to be occasionally rebuilt. Even with just 1M files, that always took a long time; but with 100M+ files?? If the storage was removeable or if you booted occasionally with another OS (or even just a different version of the same OS) then I found it was near impossible for an indexing service to keep track of all the changes.