If the man want's to spend his money . . . .
I once had a loose line that made me loose all the hydraulic fluid in the 206JR, non-event flying one of those without hydraulics.
Anyway, by the time the light comes on you will have already noticed that you have a HYD problem.
If you wan't to purchase something cool for your helicopter, buy one of those fancy Garmin GPS's, or the new LED NAV and ANTI COLL lights, those are pretty neat.