Looking for a cheap usb/aux interface
 

Hi, as the title suggests I am looking for a basic interface that can be connected via the spare port of the stock radio (ISO 10487, correct me if i'm wrong) and has aux and usb options. The car in question is a 2004 MPV. I don't need anything fancy such as bluetooth, text support etc. and wouldn't like to spend a lot more than 30$ on the gadget. So far the best candidates seem to be the Moonet adapter
the Amooca adapter
and the yomiko adapter

which are all represented in several versions that vary in price by a few dollars on amazon. Does anyone have any experience with these adapters? Is there something I should avoid/know when buying one of these? Do they perform poorly for no obvious reason like many cheap gadgets we've all bought at some point? Is there a reason to spend more money on this?
Thank you for your time!

I bought the "Nulaxy Bluetooth Car FM Transmitter Wireless Audio Adapter Receiver KM22" on Amazon which apparently is listed below $12.00 today. I paid 24.00 a year and a half ago. I bought it to listen to audiobooks on my iPhone in a MINI convertible. It plugs into the lighter and plays through FM on the car stereo. I only use it to link to the iPhone and to connect to the phone for calls. I have not tried to use the USB port or probably 75% of its features.

The sound quality exceeded my expectations, I cannot comment on the quality of the phone connection. The MINI convertible is not a good place to try to make a phone call!

The only problem I have with it is it takes up the lighter port and I also need that for the GPS which I now have connected to the port in the trunk.

I recommend you base your decision on Amazon reviews. They are typically based on a more detailed analysis than my limited use of the product.