I let mine warm up everytime. I can be patient for 5mn if it saves me a few hundred dollars!

 

From everything I've read an EFI "newer" car needs about 30 seconds of warm up, I let my quads warm up for a minute or two, anything else is a waste of gas IMO. I've also read different reports that it's best to warm up by riding/driving at very low RPM's for a minute or so to allow all the other moving parts a chance to warm up. I doubt there is much harm that will come from a short warm up period EFI or not.

 

I have always warmed anything i drive before going no matter how warm it is out. It has been a practice since my first engine build. Oil flow is my most concern. But you know, I know people that will start there car in below 32 degree temps and drive right off and never have a problem with there car. Now why can't I be so lucky. I know when it gets cold oil gets thick and this can cause oil starvation if not allowed to warm up. But there is always that person who gets away with it.