I decided to replace the Home button of my iPhone 4 because when I pressed it, it was not respond properly to the action.
The repair was very god, I followed the guide for the Home button replacement in your site, and it was very clear and easy. It take me a bit long, about 2 hours and 15 minutes, but I was very proud to see the final result. I find difficult one of the first step: the removing of the battery (excessive amount of glue). :)
p.s: sorry for my English :D