Can the human one be controlled by a thermostat, and if so, can you get it to go low enough?
Bear in mind that a human's normal body temperature is above a Corn's ideal maximum. I doubt you could get a human heat mat to run below normal human body temp - it would feel cool to us otherwise, which would be pointless for human use.
Perhaps someone will be along shortly who has actually used one, but my feeling is that I'd stick with the specialist reptile heat mats.