PETERNSTEINMETZ  This is a 32 bit control panel, so requires a restart of System Preferences under Snow Leopard -- annoying, but works.

As to Proteron, LLC, it is listed as an inactive corporation by the state of Nebraska for non-payment of taxes. The registered agent, Neill Mollard, of Omaha, NE doesn't appear to have a phone number in whitepages. But perhaps someone in Omaha might be able to reach him.

The other developers, Ammon Skidmore, Samuel and Matthew Caughron seem to have moved out west. Would be nice to get the source or an update, that is for sure.  
(Version 2.6)

PETERNSTEINMETZ  Yes, most definitely past time to abandon stuffit. I think it was 2 versions back I gave up, when I discovered that my last remaining use, an encrypted archive, could be accomplished as easily or better by an encrypted disk image.

Now they want a c.c. number to try the demo. What a scam.

The user interface they have gone to is terrible as well, very un mac-like.

Avoid it.  
(Version 2010 14.0)

PETERNSTEINMETZ  I've been a long time user of Interarchy (and prior to that Anarchie) and liked the older versions rather well.

I have to recommend CyberDuck instead these days. Although Interarchy transfers are fast, the developer who acquired it really isn't maintaining this. The 9 update appeared to mostly a reason for the new developer to charge everyone something.

The new UI is not the most intuitive, in my opinion.

Cyberduck is perhaps not as polished and not as fast, but it is free and is maintained.  
(Version 9.0.1)