Oh, I'm not disputing your observations (just contradicting 'em

) - I know LOTS of users have reported the same problem. In fact, I left X1 for Archivarius two years ago for that reason. Somehow, when I reinstalled X1 five or so months ago the problem had vanished and I've yet to see it. However, I do rub my rabbit's foot nightly before bed! X1 is set to index automatically on my systems and is set to start automatically as well. TextExtractor is the culprit when there IS CPU activity from X1 on my systems, but it rarely exceeds more than 15%.
FWIW - I have Indexing Priority set to "Delay indexing up to 60 minutes if PC is in use" and indexing updates set to 60 minute intervals. I have the "Index local files in real-time" option enabled as well.
I have about 60GB of data indexed on each machine (they largely mirror each other) of which 10 GB are PDF files and a further 10 GB are powerpoint presentations and word documents.