Disco drivers are always worried about overheating.

There are a couple of ways you can start and go. One is to start and drive off at high revs and loads on a cold engine, which isn't good. Or you can do it right and start the car, give it 30-60 seconds to build oil pressure then drive gently.
A water cooled engine warms up quicker when under load. So by starting and driving gently at first you warm up faster and get to best mpg faster.

 

I can't say I have ever seen an aftermarket RS that monitors engine temp or oil pressure, however almost all of them tap into the tach signal and monitor it, but I think it only does this to verify the engine is running, and I believe the signal can fluctuate quite a bit before the system shuts itself down. Run times are programmable 15, 30, 45 is standard for most of them, brake shut down is required by law in all 50 states. I can say that I don't see them being too bad because I know GM for sure (I think the other 2 of the big 3 as well) offer factory remote start as an option on most cars and trucks now (my parents 2009 Pontiac has it with a factory key fob complete with RS instructions on the back of the remote).
I use mine about a dozen or so times a year, summer days over 120 and winter days under about 40 which there are on average only a handful of each here. I mainly have it because I am in the business and I use it for presentation for customers.
ultimately though yes Antichrist is right if there is any kind of problem while the truck is remote started it could end up costing big bucks but I think most people feel the convenience of a warm vehicle (or cool in the summer) is worth taking the chance of letting the vehicle run unattended for a few minutes now and then.

 

There are a few problems with the "drive it gently" theory, where do you live that you can drive it gently until completely warm?
I live less then 2 miles from the expressway, top speed it 35 in that distance, when its 0*F if I drive it straight away its not up to temp before I need to get up cruising speed.
Coming home from work...less than a mile until the expressway.

Now here is a little unscientific experiment that I did last year, put whatever value into it you want...
For one week last winter I started the engine, let it idle for 1 min, then drove to work.
Same thing coming home, no deviation from my route other than the Shell station on Thursday, 150 miles and got ~10 mpg.
Next week, let the engine idle for 10 min, then drove to work, same thing coming home.
Exact same route, only deviation was the Shell station, same 150 miles, but now I got ~15 mpg.
So, you guys can do whatever you want, but I am letting my truck warm up for 10-15 min depending on how cold it is.

 

I get ready for work, except for my boots, with wooly Crocs on I run out and start the truck. Feed the dogs, put my boots on, grab my lunch bag, out the door. Hit 7-11 at the end of my street, let the truck run while i'm getting my coffee, then hit the road for work. 10 miles one way. after work, start the truck, then as Spike does, check the e-mail, facebook, etc. then off home. no running problems, and fuel seems to last a bit longer too!

 

You don't have to drive it gently until it's at operating temp. 35mph for 2 miles is more than enough.
I wouldn't base any mileage figures on a single fill-up, unless you have a real time mpg readout.
When really cold, like -20 or something, I'd start it and let it idle while I scraped the windows.

 

Like I said, non scientific test.
I check my MPG every week.
I get fuel once a week.
At the exact same gas station, Shell.
I use the same fuel, Premium.
I get high 14's to low 15's every week.
I drive the exact same route every week.
Stopped letting the truck warm up, MPG dropped.
Go back to letting it warm up, MPG went back to normal.
Nothing else changed besides the warm up time.
If you want to drive in a cold passenger cabin thats fine, I choose not to.
I dont scrap windows either, turn the defroster on, fan speed on two, come back in 15 min and the windows are clear.

 

There is the ONE advantage to owning a DII - two minutes on defrost and the front and rear glass is clear.

 

Until you have to buy a new heated windshield...$1200+.

 

Not just DII's, you can get heated windscreens for D1's, they were a ROW option. I have one in my '95.

 

Already did one. Stone chip started to cloud right in the line of sight! Didn't know that they were available for the DI, that is interesting.