At first glance, StuffIt Deluxe 2010 seems like a great thing. But is it really worth the money? When I reviewed it, I couldn't justify advising any friend of mine to spend so much on an application that doesn't do anything unusual enough that a free application can't suffice.
At a Glance
--Send large files to your friends with 2 GB online storage space
--Create .DMG files from menu
--Supposedly improved compression
--Other than opening proprietary formats, nothing unique
--Yearly subscription fee of $29.99
Features
The same classic features and ability to unarchive many file types, including .sit, that existed in previous versions of StuffIt still exist in StuffIt Deluxe 2010.
Included with the new software are options to compress and upload files to a secure online server rather than attaching them to your email; the email recipient is then provided with a link to download the file.
There are also plugins for Adobe Photoshop Lightroom, iPhoto, and Aperture.
But for the extra expense, I find that taking the extra step or two necessary to compress and upload these files with a free (and streamlined) app isn’t much work after all.
Installation and Usage
The process of installation went relatively smoothly for me, and the application itself wasn’t clunky, but there were several different applications included to do things I don’t need to.
I didn’t run into any major issues with the application -- my beef is simply that there’s nothing special here that you can’t get with a free application!
Free or Cheap Alternatives
Between UnRarX, The Unarchiver, and 7Zip, I can open just about any compressed file I need to open. For those rare and annoying .sit files floating around, a free older version of StuffIt will suffice. To share files, try Dropbox -- you get 2 GB of storage space for free. To create .DMGs, use Disk Utility, built into Mac OS X.
License/Pricing Info
--$79.99 is the steep introductory price to purchase StuffIt Deluxe 2010.
--$29.99 is the price you pay if you upgrade from another version.
--$29.99 is the yearly subscription fee to use the 2 GB online storage space.
StuffIt Deluxe 2010 can be downloaded from http://www.stuffit.com/mac/index.html.
Conclusion
It's solid and won't give you any problems if you do invest in it, but don’t rush out and buy this application. There’s nothing so special about it that it warrants even $30, let alone that much per year!
Instead, look into some free applications that can perform the same tasks, often faster and just as well.
Rating
Rating 
StuffIt Deluxe 2010 performs adequately but isn’t really useful enough to justify the price.