I wanted to fix my iPhone 4 back to original condition because I may want to sell it when the new iPhone 5 comes out.
There are cheaper fixes available but I didn't want to wait for parts to be shipped from Hong Kong and I didn't want my iPhone to be lower quality than original. The feed back tip's and online instructions were very good. I inverted some tape on my desk and wrote the step numbers on the tape and also notated the screw sizes where applicable and set the screws on the tape which made reassembly easy.
A large magnet is handy to recover dropped screws and tweezers are a must for re-assembly. It came out like new, I'm very happy.