Stuffit Expander IS *NOT* a reliable RAR expansion tool. It has failed decompress RAR files for me and my clients years.
Having dealt with the whole Stuffit line for a decade or so (yeah I'm a old Mac guy) I have found it can produce corrupt archives, leading to costly re-production of projects.
Instances of corrupted stuffit archives are common to the Mac community.
New Stuffit products often cannot open stuffit archives produced by older versions of Stuffit.
I maintain an old OS 7, OS 8 and OS 9 Macs (with comparable OLD versions of stuffit) for the purpose of opening old stuffit archives.
Surely a company that has proprietary ownership of the Stuffit format(s) could a least maintain a commercial product that that can can Open ALL the crazy formats they have produced over the years.
Finally a warning: ZIP, RAR, GZIP and the many other loss-less compression formats should never be run though stuffit ONLY perhaps if a tested uncorrupted backup exits, the likelihood of corruption of by stuffit, of these open compression formats is extremely high.
I look forward to any comments from the current and past developers of stuffit - they have a lot too answer for.