I would do it if they are offering it for free. I've never heard of permaplate but the protection coating all seem to be about the same thing. The coating offered at my dealership allowed them to spray paint the hood, light it on fire, and it just wiped off! My dealership wanted $1500 to do the coating inside and out. I opted not to get it due to the cost. Instead I used an over the counter sealant from turtle wax. It was cheap and says it last 12+ months. Next go around I plan on using optimum opti-seal which is suppose to last 2-3 years.
Keep in mind that if you ever want clear bra installed on the front they have to buff off that dealer applied coating.