Mega or Due?

[Tmp2k]

I'm just planning a rather ambitious project, without boring everyone with too much detail here's roughly what it will do...

12v automotive project
read car sensor data directly from OEM sensors, speed, rpm, throttle pos etc
actuate throttle with a servo, lights, horn etc
control lots of PWM RGB LEDs
control LCD display, and 7seg HUD (may use a seperate arduino mini pro for this unit)
take input from several buttons

possibly..
rfid reader
bluetooth/wifi connection


So what at the pros and cos of the Due Vs the Mega?

Will I need the extra processing power of the Due?
Will the Due have a higher standby current than the mega? (it will be on while my ignition is off)
Will the Mega be better for interfacing with a wider range of sensors? 5v Vs 3.3v


So far the Mega looks like the better option to me, but can the Due do anything the Mega can't that I would need for this project?

[CrossRoads]

Doubtful - Depending on the IO count, you may even be ablet drop down to a 32 IO pin '1284P with its 2 serial ports, I2C to the LCD display, SPI for a shift register for the HUD (or MAX7219 if numberous digits).
Make up a firm list to start.

[Tmp2k]

I have over simplified it a bit, but I didn't want to be here all day typing up my project.

I've started planning it out and these are the requirements I've got so far..

Inputs
-------
9 digital
1 analog

Outputs
---------
15 digital
10 pwm


Comms
-------
2x serial



I'm sure there will be more stuff that I need that I just haven't thought of yet lol.

[CrossRoads]

So that's 39 so far, pushing into Mega territory without adding extra  hardware.
Does Mega support 10 PWM? May do 12 or 16, I haven't looked at one in a while.

[Tmp2k]

Yeah both Mega and Due  have pretty much the same I/O spec.

54 digital
12/14 pwms
4x serial

I'm just wondering what the Due has got going for it over the Mega