To be fair, this is the first contact extension I m looking for, so I compare this only to Joomla's native contact form. I don't understand why so many people rated it with 5 stars since this form, although it is very good, is lucking some features such as a nicer look on Captcha system and a possibility to translate the captcha messages:
"Please enter the following security code:"
"Not Readable? Change text".
The tutorial is missing info about how to use the Multiple Captcha Engine plugin.
All in all, I believe this is a good extension with many choices, but it is still not perfect to receive 5 stars.