I fixed them because I got tired of listening to my wife complain about her broken iphones
Pretty well overall, the iPhone 4's guide has an unnecessary step that added about 5 minutes to my resolution
Do not remove the front facing camera for the power/lock button replacement. This step is unnecessary and only wastes time.
iPhone 5 Power and Lock Button
iPhone 4 and 4S Power and Lock Button
iPhone 4 Home Button Assembly