I can share my experience. When I decided to purchase AUX Link, I compared all the prices and it's really much cheaper to buy it at the official online shop AUX Car Kits. The delivery took just five days. At first I decided to try to install it myself, but had problems extracting the OEM car stereo. I didn't have the right tools, so finally I had it installed in the nearest auto workshop. It took just 10 minutes. So far I'm totally satisfied with this kit.
Advantages:
- supports iPod, iPhone, iPad, USB, SD memory cards, and there is also a mini jack for other mobile gadgets (MP3 players, Windows-based and Android-based smartphones, tablets, laptops, netbooks, PSP and so on).
- great sound
- you can use it as a charger
- with optional Bluetooth dongle can be used as a hands-free kit
- music control with buttons on the steering wheel and buttons on the car stereo (very convenient)
- read all music formats
- free and fast delivery
- occupies very little space and doesn't spoil the interior
- now I can listen to all my favourite music without carrying piles of CDs.
Disadvantages:
- relatively expensive as I also purchased additional Bluetooth dongle to use the adapter as a car hands-free kit
- couldn't easily extract the head unit so I had to go to service center
But taking everything into account, I believe it's a good price-quality ratio. So from my point of view it's worth buying.