The reasons I purchased this module: A trial version was available. Nice administrative interface. Good documentation. Most importantly - it works.
I had tried other modules. One just plain didn't work when trying to redirect based on roles. Another other did not handle logins that first require a user to enter the verification code sent via email upon registering. How the heck do you try to sell a login module that can't account for a site wanting to use verified accounts? I started emailing others to ask that question (when a trial wasn't available) I found others that couldn't.
In addition, when DataSprings sent a follow up to the download trial, I responded with a note letting them know I purchased this module and was very happy with it. It was then follow up with a thankyou and another person on staff offering some unsolicited tips that helped me with the site.
Good support and a good product. Yes, it may cost more, but you get what you pay for here.
I evaluated four blog modules for our site. SunBlogNuke v4 is intuitive, easy to setup, easy to learn all while being very powerful. This is by far one of the best user interface designs you will find. A great value compared to others modules.
I wanted to give 5 stars, but just couldn't quite do it. Once you get use to the interface and all the possibilities, this is a great tool for developing apps in DNN.
The reason for not going with 5 stars is documentation and examples. While there is a 220 page manual, useful details/specific examples that make life easier are missing.
The online videos at their web site are invaluable and they need more. The community forums are helpful and I found they responded in a reasonable time. The developer community is small so the overall activity is low relative to other forums I've used.
Overall, I found this to be a solid module that has allowed me to do things in DNN that I would have been able to do otherwise.
I have just begun to scratch the surface of this module and already I'm very impressed. Easy to use and more importantly great documentation!
Did I mention great documentation. Other module developers take note, this is how it's done both on ease of use and documentation.