Considering ordering an Android HU to replace the current OEM setup and from what I can tell from searches, Erisin seems to be the best bet. I'm after a bit of advice before I pull the trigger though. Current set up is 2007 Avant S-line Spec Ed with Non-Bose Symphony 2+, MFSW, OEM bluetooth and SDS, and the normal single colour DIS. Also no external roof aerial (just the rear quarter glass ones). I'm not really worried about DAB etc. My main requirements are the ability to play MP3s, use handsfree phone, Google maps and Torque Pro. My questions are: 1 Do the Erisin models support the full MFSW fuctions (obv volume etc, but also the voice/phone controls)? 2 Ditto the DIS? (phone call and track details etc displayed in the top section) 3 What else will I need to get/do wiring-wise, or is the Erisin genuinely plug n play? (Obviously the rear speaker issue is the main one which seems to crop up. What's the situation fitting an Erisin in a non-bose set-up like mine?) 4 Can I use the factory roof mounted HF microphone, and if so will I need to splice the Erisin mic wiring into the OEM one? 5 Where/how have folks fitted the GPS antenna that comes with these units? 6 Am I right in thinking I can tether the Erisin to my Android phone for 3g/4g data (set the phone as a wifi hotspot then connect the Erisin to it)? and finally: 7 Given my main requirements list above, which unit would people recommend? (leaning towards the 7878A at the mo) https://www.erisinworldwide.com/hom...ifi-obd-dvr-dab-for-audi-a4-s4-rs4-b7-b9.html https://www.erisinworldwide.com/hom...tem-with-gps-satnav-dvr-for-a4-seat-exeo.html https://www.erisinworldwide.com/hom...igation-dvr-dab-radio-system-for-audi-a4.html https://www.erisinworldwide.com/hom...cd-sd-for-audi-a4-s4-rs4-b9-b7-seat-exeo.html https://www.erisinworldwide.com/hom...t-nav-for-audi-a4-s4-rs4-b7-b9-seat-exeo.html https://www.erisinworldwide.com/hom...ps-player-wifi-4g-dvr-for-audi-a4-s4-rs4.html Sorry for all the questions (just trying to get all the info before splashing out, and would prefer to be able to get the job all sorted in one session when I come to fit it), and thanks in advance for any help!