You'll be very, very happy. Just make sure you don't let it walk away, a very popular item for the less than honest. Whelen has been the industry standard for public safety for many years. Just look here to see their warranty. All that and a 24 hour turn around to boot. Not too many other lighting companies can compare in my opinion.
I would recomend finding another way besides the mag mounts to secure it- while they are sturdy there is a good chance of that light sliding(or any light for that matter) if just being held down by the magnets. I have seen too many blue lights ruined that way, or even by taking a corner fast- they slide right off the vehicle and if your lucky break the cord so they don't get dragged by the vehicle. The other thing is that te less than honest crowd likes mag mounts since they are an easy lift- just ct the wire and run with it- especially that size.
Other than that its a great light and you will like it.