Centaurus
I suspect the ship you mention is the one previously used by the Spanish navy to fly their Harriers (Matadors to them). They used the ski-jump for all the usual Harrier reasons.
As to choppers I am no expert but they can lift more with a rolling takeoff due to translational lift from the rotor disk. Goodness knows whether all the issues of hitting 2-3 g on the ramp just to gain a bit of free time in the air while they accelerate to flying speed would be worth while I can't say but if asked for my best guess I would say a resounding no. The advantages of a ski-jump are totally dependent on being able to accelerate rapidly off the end (.7g ish - the more the better) Does not sound helicopter stuff to me.