The home button on an iPhone 4 was almost completely unresponsive. It was a real pain. Also, the wifi signal was very poor.
I used the ifixit guide and the repair went real smooth. I minimized any direct contact with the screws and other metallic contacts by using the tweezers the entire time. The phone also had a weak wifi issue. I improved it by making the grounding screw had good contact (it might have lost its solid grounding after being dropped), but the signal is still not as strong as it should be.
The whole thing was a real straight forward process. I had no problem fixing the home button which was my main objective. Nonetheless, the process took me about 2 hours because I was playing with the wifi antenna (trying to understand what was causing a separate poor signal issue).