Hi UIK
I installed Pioneer AVH-X8500BHS, got it on ebay from US. Under 500$ delivered. The idea behind this was, the unit was meant to be able to mirror the phone, and it does, but only pioneer approved apps. There is a way around it, but it gets complicated. I would highly recommend a unit with MIRROR LINK technology, true mirroring of the smart phone. Very useful.
Another thing that really ****** me off.... the USA retards don't let you use video features of your head unit unless car is completely stationary, ie, you must engage park brake. Which is usually remedied by grounding the park brake wire, if that doesn't work you have to install a simple relay, so park brake gets grounded only after the car starts. But to my surprise that did not work work either. So after reading lots of forums i figured that they went step further. So what they want you to do is to stop, put the car in park, engage park break, then release it and then engage it again... WTF????? Only an american sicko can come up with something like this. Thankfully I found this Russian dude that sells double pulse relays on ebay for 20$, it works perfectly.
Installing any brand name unit will be essay, you just buy a connector harness from auto barn, tell the brand of the unit and brand of the car, it is almost plug and play (you have to connect few wires yourself, but easy to figure out)
You also have to buy fascia, plastic cover around the unit. Ebay, 50 $. You can get steering wheel control adapter, but I think it is a waste of money. If you don't get (don't, you don't need it) you have to ground Pink wire from the diagram above- Steering control ground on the connector 3
And i just couldn't figure out how to make the reverse camera work, i tried several things, nothing worked. But you can get the aftermarket camera that fits into the same spot as the factory one, and it is so easy to connect, and works perfectly.
The pioneer that I got works excellent as a stereo, it has two AUX inputs, two USB inputs, HDMI, AVI and so on, I can hook all of my gizmos to it. It also takes SD card, I use that as opposed to cd's, much easier.
Sound is excellent, it has inbuilt amp, and I have type R Alpine 6'9 all around. If I choose too, half of the Brisbane knows when I am approaching.
But if you get something with MIRROR LINK, you don't need the GPS unit, you just get the navigation of your phone.
Good Luck!