I was a bit hesitant when it came to purchasing Gravity Forms but in the long run I'm glad I made the jump.
The plugin is simple to use, has heaps of features to make just about any form you want and the support is excellent!
Support is so great that even before I purchased the plugin Carl Hancock of Gravity Forms put together a dummy form so I could see a final outcome.
I use three forms throughout my site for customer support:
10 out of 10 for Gravity Forms!