45 minutos - 1 hora
My iPhone 4 was not charging or syncing over the USB connector. I was pretty confident it was the dock connector and not the battery as syncing wasn't working and it also gave me a little warning that it was going out as the connection was a bit temperamental just before going out entirely.
The repair was a bit more involved than expected, as you work from the back with the iPhone 4 rather than the front as with the 3G/GS. I'm impressed with the construction of the 4 compared to the 3G. It seems to be a bit less sensitive to this kind of monkeying around. There are a couple areas where extra care is definitely warranted and the howto video is good to point that out.
I love how well the replacement part comes ready for installation with all the of the adhesive already applied with easily identifiable sticker backs. The little microphone cover is probably the most sensitive part of the entire operation and requires special care to make sure that the cover is properly in place on microphone and the little rubber tube is inserted in the plastic receptacle. I'd say this is a medium difficulty repair, but easily accomplished if you've done any mac mini, ipod or iphone repairs previously. I was done in about 20 minutes.