Light colour is perhaps the most essential aspect of both of these ranges, so let's start by getting to grips with colour temperature. Light colour is defined by its temperature, which is measured in Kelvins (K). Simply put, the lower the Kelvin rating, the warmer (yellower) the light colour, and the higher the Kelvin rating, the cooler (whiter) the light will be.
Bearing this in mind, with a colour temperature of 4200K, the Philips WhiteVision Ultra produces a whiter, more stylish light colour than its predecessor, the 3700K Philips WhiteVision. 4200K is not only a tremendous increase to Philips' standard halogen colour temperature of 3200K, but it also has the highest halogen Kelvin rating - and therefore the whitest light - allowed by law on public roads.
The WhiteVision's 3700K is still an improvement in comparison to a standard Philips bulb. But, ultimately, if you're looking for a stylish option, the WhiteVision Ultra wins this round with its 4200K crisp white light.
The war's not won yet, however. As we'll see further on, the WhiteVision still has a trick or two up its sleeve...
Although both Philips WhiteVision Ultra and Philips WhiteVision are defined as styling bulbs, each range also offers an impressive light output, exceeding that of a standard halogen by 60%.
Each range's extra brightness is a bonus and worth bearing in mind for those looking to modestly enhance the amount of light on the road. This extra light can improve safety and comfort on the road: obstacles are illuminated more quickly than usual, and your vehicle is more visible to other drivers.
With both the Philips WhiteVision and WhiteVision Ultra achieving an identical amount of light on the road, we've no clear victory in this round. As it stands, the WhiteVision Ultra seems to have one up on the WhiteVision on the grounds of its superior style, but that may be about to change as we head into the next stage of the competition.
Just when it seemed the Philips WhiteVision Ultra was heading to a clear victory, the WhiteVision throws a curveball in the form of lifespan. The impressive lifetime expectancy of the WhiteVision reaches up to 450 hours, giving it a clear edge over the Philips WhiteVision Ultra's up to 250 hours of bright white light.
It's worth noting, however, that the differences in lifetime is due to the vastly increased Kelvin rating of the Philips WhiteVision Ultra.
The world of styling bulbs is rife with non-road legal ranges. Both of these Philips ranges have achieved road legal certification. Both the WhiteVision and the WhiteVision Ultra have been expertly tested by Philips and rigourously uphold the necessary ECE regulations (R37) to achieve road legal status.
This means that you can enjoy each of these styling bulb ranges on all public roads and highways, so you can get the most out of your headlight bulb upgrade!
It's a tight competition in terms of brightness, engineering standards and legality. Both bulb ranges have fought valiantly, but in terms of extra style, the crown has to go to the Philips WhiteVision Ultra. There's no denying, however, the merit of the Philips WhiteVision's extra lifespan. In the end, it comes down to personal preference: extra style, or extra lifetime.
Shop Philips WhiteVision Ultra here. Shop Philips WhiteVision here.