How to define best, i think whatever is suggested is from personal experience.
I have used Philips Xenon X-treme Vision gen2 D1S for 9 years now, on permanent every day.
It was brighter than factory (one bulb started to go yellow) and a better beam pattern on mains.
Around £55-60 each.
Check box should have hologram and ref. no. back to Philips to check genuine.
