Guys, I came across this unit http://www.dashdaq.com
I will be calling them on Monday and seeing if I can arrange a review of their system. The videos on their site are a bit cheesy, but I think it has GREAT potential.
Here are a few highlights... 4" color touchscreen (don't know brightness), OBDII based, can be upgraded for GPS (cost?),linux based, completely self contained unit.
Can accept phidgets (these are generic usb based sensors. I have used them in the past for other projects, and they are fantastic - anything from pressure, motion, acceleration sensors, etc...)
You can customize gauge groups, display several at a time... mixture of dials, digital, graph.
Scan and save results (I think to a USB thumb drive??)
The videos are somewhat clumsy, but for me they answered some key questions, like how responsive the unit is (sample rate for RPM, for example).
At $695, it seems like a great deal.
If I talk to them and find no show stoppers, I will try it.
Here are some vids from their site: