I know that the ratings say that the Mega has an input range of 7-12v, but I want to make sure that it will work properly long-term without risking overheating the regulator and shortening its life? I'm planning on powering all of the sensors with external power supplies, so the Mega would only end up providing power for itself. I've currently got a Pololu S18V20F12 purchased for the job, but am wondering if I maybe should have picked up the variable-output one instead...
The reason I'm asking is because I found this article when I was Googling around:
http://www.australianrobotics.com.au/news/fuelling-your-arduino-why-you-should-use-an-external-power-breakout
and it looks like anything over 7v might be too much for long runs? So I thought I'd ask the experts 