Stuffit on Windows is like soccer: No matter how popular soccer is elsewhere, it's always second to football in America. While Stuffit reigns on the Macintosh, it's never unseated WinZip from PCs, despite the fact that the Stuffit program handles zip files just fine. Further, all archivers have the same problem: Archive formats are, by necessity, among the slowest-changing in the world. It's hard to make something so prosaic exciting enough to merit buying a new version, year after year, so constant new bells and whistles need to be piled on with each new release, since the core functionality of turning last year's Excel sheets into a cryptically named file to be burned to a forgotten CD-ROM and lost at the bottom of a cardboard box full of leftover supplies from the Christmas party is pretty rock-solid. Stuffit Deluxe 2009 sure does try to make it exciting, though.
One particularly nifty feature is "Droplets": With a few clicks, you can create desktop icon that performs a standard function on whatever you drop on it (hence the name). For example, you can create one which will take a pile of unedited reviews and screen grabs, zip them up, and then attach them to an e-mail so that all you need to do is fill in your editor's name and off they go to her. As the name implies, you simply "Drop" the files on the icon.
Stuffit Deluxe 2009 supports just about every major archive format, including ZIP, RAR, tar, gzip, cbr, and a lot more. It integrates into your Windows environment smoothly, and can create self-extracting archives (.sea) which means coworkers or customers don't need to have your version of the archiving tool to unarchive your files.
Stuffit Deluxe 2009 also has optimized compression algorithms to compress even already-compressed formats, such as .jpg. I compared Stuffit Deluxe 2009 to the latest version of WinZip, using both's "maximum compression" settings and newest formats, and Stuffit produced an archive roughly 5% smaller than WinZip. A small savings, but a savings nonetheless. It all adds up.
Stuffit has a lot of "nifty" hidden just under the hood, and its compression is as good as its that of its competitors. It is certainly worth looking into.