Stuffit products have been on my Macs for years and have done a wonderful job of compressing and decompressing. Stuffit Expander shipped with all versions of the Mac up until OS X Tiger. Now that zip is built into the OS and even has extensions for keeping the Mac resource fork (newer applications don’t use the resource fork anymore), I haven’t been able to come up with a reason to keep Stuffit Expander around except to deal with files I download that are still in .sit and .hqx formats. I find that some companies are still putting files on their websites with these extensions; if the app doesn’t have a resource fork, zip it. If it does or you want to customize the look, use a disc image (.dmg) and let a user download that. I think by now users are used to using disc images. Also, the disc image doesn’t need to be zipped or .bin put on the end; just make sure your web server serves up the .dmg file as application/octet-stream.