Your options will be pretty limited due to #3, hard drive-based navigation. I believe there are only a handful of head units like that available, such as the Pioneer AVIC.
But the most difficult part of your plan is getting any aftermarket unit working in a new Lexus. Lexus cars are not very aftermarket-friendly. They use non-standard face plates and controls. I'm not even sure you will find a conventional double-DIN slot on the stack. I believe you would end up paying around $1,000 for the head unit, and about the same or more for the installation, if it's done right. The installer would likely have to fabricate a new face plate for the stack. You would probably be better off just getting these features as options on the car.
Hi - I'm planning to a buy a new 2009 Lexus when it comes out and am going to buy an aftermarket system that (hopefully) has all the features I want. The problem I have now is in my research I see lots of units that have the features, but also read lots of bad reviews from consumers of them. I'm looking for a recommendation on a unit, preferrably one of the newest models available even if it's not available yet, that covers all the bases for me.
Here's my wish list:
1) Sirius Satellite Radio
2) GOOD Ipod support - meaning full search, playlists, audio, video, etc.
3) Hard-drive or online-based GPS navigation, NOT DVD-based. Traffic support is great but not essential.
4) DVD video playback
5) Double-DIN size
6) Integration with steering wheel controls (not essential but important)
I've looked at the Pioneer's and Alpine's but all their units seem to be a couple years old, I haven't seen anything new announced.
Can anybody lead me in the right direction so I can make the best purchase in around the September/October timeframe? Cost is not a concern, so please don't let that limit your recommendations.
Thank you very much!
Greg in NJ

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