woohoo!!
Just installed a Pioneer DEH-P3100UB to replace a Sony Xplod unit that has failed for the second time in 4 years (and only had an AUX in port). The Pioneer has a USB port in addition to the aux, and I can verify that the USB charges my iPhone 3GS and the sound is terrific.
I soldered all the connections too. Looks great and sounds great!
I'm so happy to get also get rid of the Kensington LiquidAUX charger/aux combo I was using. It sounded muddy and always had this annoying whine in the background. The Pioneer has absolutely zero background noise (which I attribute solely to my soldering skills!)
I can't believe Best Buy wanted $50 for a geek squad install plus additional money for all the VW-specific accessories to make it fit. Crutchfield sold me the head unit for $20 less than best buy and its included instructions were more than adequate. Saved myself around $90