I purchased the Business Edition because we needed users to have multiple logins, but not unlimited.
This plugin is excellent! And it turns out there is even more flexibility than we expected. BTW - we are using joomla 1.5.
With the business edition, you can set the global default # of logins per user. In our case it's three.
Then you can override this by creating groups. Example user ID's 4-10,44 and 55 can have 7 logis. And you can create up to ten groups like this.
It works like a charm. This is a GREAT value program. Also - I wasn't sure of how to do some settings and had some questions. The developer provides excellent support.
Like many of us here, I've downloaded a large variety of plugins, but it's rare to find a gem like this one.
A big thanks to the developer for creating it and for the great support.