Philips Vision Plus or any other bulb with H4+ technology (brighter than regular H4s but without going into xenon-look alike blue bulbs or higher wattage bulbs) may provide a slighlty better lighting pattern, but only if your car is fitted with the original European standard reflectors. U.S. pattern beams and reflectors do not allow the H4+ bulbs to shine as they are supposed to.
If your car is a pre-93 W124 model with the made only for U.S. reflector, you will not notice any gain in brightness. If your car is a post-94 W124 with the U.S. reflector beam, you may notice a very marginal increase in brightness.
Most of the gains that owners report with these bulbs are proven to be only pshycological, according to the local dealer, since tests show that the limited scope that the U.S. reflectors allow (even facelited post 94 W124s) only a very limited gain in H4+ bulbs.