From worst to first:

I started with Duplicate File Finder from Ashisoft. It was a smallish 1.8MB download. It offered byte-to-byte comparison. Not as intuitive as the winner of this review, especially with selection assistant. Can only scan mapped network drives. Deletes to recycle bin, to give an extra chance at recovering from deleting too much. Not anything to write home about, though.

Next, I found DuplicateCleaner from DigitalVolcano in UK. It came as freeware in a similar 1.8MB. I was saddened to see it was really only a trial version limited to 50 files at a time. The scanning was not astoundingly fast (and fluff like annoying sound effects). It found 371MB of duplicates in My Documents. It is nicely accurate using Byte-to-byte comparison and "fuzzy logic." But so does...

Doublekiller from Big Bang Enterprises in Germany. It was the smallest download, less than a third of the others, zipped to 400k, 800k exe. Runs without installer which is a big bonus, no trash left behind; it could win on that alone. But it's FAST scan is really killer. Double-click to file. No reporting option, but move instead. Permanent delete. Found 300MB dupes in My Docs.