These lamps are used for the driving lights of the Elise S1 and for Dipped Beam on the Elise S2 with the early headlamps.
You can recognize these early headlamps by checking if the sidelight bulb is integrated in the main beam reflector. If so, this is the early type. If the sidelight is a seperate unit above the Dip beam projector, you will need H7 lamps.
Visionplus is one of the latest technologies from Philips. Some car manufacturers have even picked this technology as their OE range of bulbs.
Compared to a standard Halogen lamp, Visionplus generates 50% more light which results in a 10-20 meter longer beam.
Being able to look further means more time to react or decide what to do and as a result.. better safety!