I wouldn't encourage using Octane improvers in your car regularly.

To get the most out of them, you should have the car set-up for the higher Octane. This is fine until the one time that you forget to put the additive in and melt your engine.

My car, for example, is mapped for normal Pump fuel. I used to put a bottle of Octane Booster in to give me a little added safety for Top Speed days, but I don't even bother with that lately.

Don't bother IMO.