What is the best plugin to capture URL query parameters?

Hi, I have an invitation page as a wordpress page, and I'd like to be able to customize the greeting, name, company of the person that I'm sending the page to by changing the URL params.

I've found this plugin: http://wordpress.org/extend/plugins/url-params/

But it only has one review and is weak on features (I'd like to possibly do conditionals on the value of params).

I wonder if someone in the community has come across something like that?