AUX/USB/SD adapter

Moin, are you also such an absolute anti-radio person like me?? Then you surely know the problem of always having thousands of CD ́s flying around in the car… I’ve been looking for a decent box for a long time, where I can connect my phone to it, or at least let music play via a USB stick. Who made himself smart there, should definitely know the “Grom Box”, however, with the (at that time still) good 300€ more to Buche a Is a lumberjack Another alternative would be these “FM-transformers”…but I’ve only heard about this so far. Has anyone found a good alternative?? If so, always get out of it! I just found this here on eBay:http://www.ebay.de/…/250864502878?… what do you think about it? Is annoying that it can only get electricity over the 12V connection, but at least better than nothing….or? Greeting!