I think it is worth it. The "airbrakes" as we call them are not really scale anyway since on the real plane they would not go up in flight. If you locked the top half even with the wing you still get some of the drag common with split flaps. I have yet to fly mine without a head wind to see if the airbrake action is worth it. As for the weight, the plane weighs a ton already, what's a couple more servos?

If you do hook them up make sure you do some mods to the horns and the mounting area, the stock set up is not very strong.