I'm looking at getting a
MCS. Instead of the expensive NAV sytstem I want to get this and replace the radio. Has anyone tried this or a similar product?
http://www.speedsound.com/pioneernavigation.html 
NAV-SYS900DVD
Navigation Package System
$1,899.95
Order Now!
AVIC-90DVD
8.5GB Dual Layer DVD Navigation System with DVD Playback
New Entire US & Canada DVD Map Disc [CNDV-20] (Excluding Hawaii & Alaska)
Ultra-Slim Built-in DVD Video / ROM, CD Compatible Slot-in Player
Built-in MPEG 2 Decoder for DVD Video Playback
High Performance 32 bit RISC CPU & High Capacity 32MB SDRAM
Exclusive Graphic Processor for Fast & Smooth Graphics Rendering
Exclusive 32 bit Positioning CPU
3D Hybrid Sensor for Distance Correction on Slopes (Gyro & G-force Sensor)
Upgradeable High Capacity Flash Memory Operating System
Built-in PC-CARD Slot (PCMCIA type2) for downloading images & store registered destination points
Voice Control interface (recognition/synthesis) for "Eyes Off" operation of system
New Multi-Function AV/NAVI Remote with 10-key (for CD Receivers AV Receivers and DVD Players)
8 Channel GPS Receiver and Antenna
New 26P RGB Cable (6m) is included for use with AVH-P6400CD and AVH-P6400
6.5" TFT Active Matrix LCD Color Screen
Widescreen 16:9 Aspect Ratio
5 Selectable Viewing Modes
Fully Motorized with Display Angle Adjustment
AGLR (Anti-Glare, Low-Reflection) Coated Screen
New Intelligent Dimmer Control
Picture Adjustment (Brightness, Contrast, Color, Hue, and Dimmer settings)
Full Audio/Video Inputs for System Flexibility
RGB input (New 26 Pin) for optional Navigation System (AVIC-90DVD)
For AVIC-9DVD, CD-RGB600 & CN-DV20 is required
A/V-Bus Input (for use with SDV-P7 or XDV-P90 DVD Player, and GEX-P6400TV TV Tuner)
Composite AV Input (AV1)
Automatic Switching capability for Reverse Back-Up Camera use
Composite Video Output
Ultra-Slim Profile Built-in CD Player
Compatible with CD-R & CD-RW
1-bit D/A Converter
AGC (Automatic Gain Control)
Disc Title Memory (48)
Supertuner® III™
24-Station/6-Button (18FM/6AM)
BSM (Best Station Memory)
EEQ™ Performance Chip
3-Band Parametric Equalizer (Adjustable Level, Frequency, and Q Factor)
5 Factory and 2 User EEQ™ Presets (Super Bass, Powerful, Natural, Vocal, Flat, Custom1, Custom2)
Source Custom EQ Memory (Independent Custom Memory for each source)
Selectable Loudness Control (Low/Mid/High/Off)
SFEQ (Sound Focus EQ)
Additional independent Bass / Treble control for Front / Rear
IP-Bus Control
XM Satellite Radio Control (Source Control)
8-character display (no scroll) for artist name, song title, album name, and category
Scrolling available for ADF (Additional Data Field)
MCD Controls
TV Tuner Control (GEX-P6400TV required)
DVD Control (single SDV or XDV player)
Auxiliary Input (CD-RB10 or CD-RB20 required)
2 Unexpected (External) Unit Control
Rotary Volume Knob
MOSFET50 (50W x 4-Channel High Power)
Hi-Volt Preouts x3 pair (Front/Rear & Sub or Non fader) (4V) Two-Way Crossover
Front/Rear HPF (50/80/125Hz, -12dB/oct)
Sub-Out LPF (50/80/125Hz, -18dB/oct)
Sub-Out Level (-12dB to +12dB) and Phase Control
Independent Subwoofer Output (Selectable to Power and/or Preamp Outputs)
Additional Features:
Full-Function AVH/DVD Card Remote Control
Detachable Face Security™
Attenuator
Navi Guidance Audio Mixing