Hi - personally I have just been down the whole road of what to do to play my phone music - streaming, blue tooth, hands free, charging USB etc. I'm not inexperienced when it comes this this stuff and did loads of research but even so...
1) I bought a £10 lead which was supposed to work but didn't work properly with newer HUs, returned and got money back.
2) Bought connects2 device but found it didn't work properly with iPhone 5. After speaking to their very good support people returned for a refund.
3) Also bought & returned 2 lightening connectors that, as they were not Apple, didn't work properyy.
4) Nearly bought one of the older OEM headsets but stopped myself!
So do we have a happy ending to the story...Yes.
Ditch the cables and add-ons and messing around - In the end I spent £58 on an eBay Sony MEX-GS600BT and new fascia plate at £8 and installed (in the dark) in about 2 hours. I am over the moon about it, It does everything and does it well, sounds great, blue tooth, streaming, mic, syncs with iPod, USB connector, displays song data, does everything a parrot does with the same ease (almost) blah blah blah - its the dogs!
If you can face having an aftermarket unit save your time and money and go straight for a decent Sony or other brand that has theses features (MEX range is very good - most can be set to the Alfa "red" display). You will spend a lot less money, less frustration and I don't think you will be disappointed. Use the guide on here for installation - its good and its 99.9% spot on.
(HOW TO INSTALL AFTERMARKET HEADUNIT - a guide for 147, 156, and GT).
Only 1 caveat is that I choose not to spend the £25 on the steering control unit, I may do at some point but some units have this inbuilt as standard. Personally I like a proper knob . Push button (and touch) is just not not as positive or safe (touch) so its doesn't bother me.
P.S. I don't have an affiliation with Sony