I have used Stuffit going allt he way back to 1.0 but I stopped updating Stuffit Deluxe when I upgraded to 10.3.0 and stopped using it about 2 years ago as fewer and fewer mac developers use the .sit or sitx formats anymore preferring instead tar.gz, zip or dmg as their formats of choice.

The MacOS has had dmg compression around for ages through Disk Copy, zip compression has been built into the MacOS since 10.3, and if you feel like messing with .tar and .z there is always the terminal for older MacOS versions and Archive Utility for 10.5 and higher.

Why spend money on a program that doesn't do all that much when there are freeware alternatives like The Unarchiver and shareware ones like Springy, iArchiver, and StuffIt Standard around? Especially as Stuffit Deluxe's only major use involves a format fewer and fewer people even use. Segmentation is of limited use and with bigger files and faster connections 20% better compression is not as impressive as it was in years gone by.

As sad as it is Stuffit Deluxe's time has passed. Time to put it out of its and our misery. Your wallet with thank you.