Did you need to do any dash disassembly for the head unit?
I have the basic head unit; the JVC R900.
Did they install an antenna into the windshield for model year 2010?
I can't say; FM reception is not great
Also, i was thinking of getting the base head unit and upgrading to a better GPS/iPod controller head unit. Safe to assume, the GPS antenna will need to be installed. So, I'll probably need to wire for GPS under the dash.
Also, where would a subwoofer go, and how big can it get?
I did the same but, when the car arrived and I looked at the effort and then the performance of the basic unit I reasoned this; too hard!!! (anyone want a cheap, unused Kenwood KVT-514+BT+GPS?)
The JVC unit has reasonable iPhone/iPod control and they wire a USB to the center console. Ten minutes work and you can drop a standard iPhone USB plug into the iPhone dock that TM provides, I used a little double sided tape to mount it and stuffed the gap with foam to create a neat and efficient iPhone dock.
I'm planning to install (soon) these sub woofers
http://www.tb-speaker.com/detail/1208_03/w5-1138sm.htm into the rear speaker locations. I'll use a low pass filter to create bass/sub-bass at the rear, mid on the dash and treble from the front. I'll post my results; so far, mid and treble up front is installed and working well.
My only complaint with the base unit, and this may be more a Roadster 2.0 issue; the microphone for Phone integration is poor, even ineffective. I'm not fussed about FM, I get better reception on AT&T 3G via my iPhone!
WRT Navigation; I'm using the iPhone with 'CoPilot Live' It's ok, you can listen to the iPod and navigate at the same time but GPS sensitivity is modest at best.
One note of warning; when you set this all up you'll need to get used to wrangling a JVC head unit, its bluetooth and the iPhone; it's all a bit disjointed at first but does come together. I start (boot, engage, init.?) the car then wait a moment whilst the bluetooth connects - this allows the iPhone to stream audio to the JVC but that's not what I want... After a few seconds I drop the iPhone into the dock and start WunderRadio to listen to the world or use the JVC unit to navigate the iPhones iPod.