I suspect Undelete 360 only scans directory structures and does not perform the kind of intense block-by-block scan used by other products here. To begin with, it returned a list of potentially recoverable files a great deal faster than the competition -- which seemed like a good thing on the face of it, but also implied a superficial search. The program also didn't do as good a job of recovering the files -- half the time, files were reported as "overwritten," even when the very same files were restored by other apps reviewed here.
Worse, Undelete 360 seemed to be just about useless when confronted with a quick-formatted drive. When I performed a quick format on my media and let Undelete 360 scan it, it turned up nothing -- and again, turned up nothing a little too fast for my own comfort. No options appear to exist to force the program to do a deep search for files from the beginning.
There are a few handy features, like the data-wiping tool reminiscent of the one in Recuva and the ability to recover alternate NTFS data streams. But those fall flat in the face of Undelete 360's much larger weaknesses.
A good interface and a nice preview system do not compensate for the program's inability to deal with anything more than recently deleted files.
Undelete 360 worked best when dealing with recently deleted files, but anything more ambitious than that (e.g., quick-formatted media) was beyond it. CardRecovery's biggest limitation was the limited range of file types it handles: It's designed mainly to recover files created by cameras and almost nothing else.
Recover My Files may be costly, but I liked its tunable scan function; its professional-level support for devices like RAID drives may come in handy. Remo Recover is functionally similar to Recover My Files, but it turned up a high number of false positives during testing.
The biggest surprise was how two of the best programs cost nothing to use. While PhotoRec was the least novice-friendly -- its text-only interface could scare off the uninitiated and its documentation is spotty -- it was also one of the most powerful. Recuva was likewise quite strong and wasn't lacking any functionality in its free version.
As a result, I recommend PhotoRec for tech-savvy users and Recuva for everyone else.