There are 3 (or even more) types of comparisons to make.1. Placing a HID Xenon bulb or a LED bulb in a halogen reflector. Placing a HID xenon bulb in a halogen reflector housing is usually by default a bad idea because of stray/blinding light for oncoming traffic. LED bulbs can be a bit better because of the placement of the LED's on base and the adjustment option. But this depends a bit on the headlight/reflector shape. We have quite good results with our AvantiLED bulbs.2. Placing a LED bulb in a HID/xenon projector. Almost always a very bad idea, light output and pattern are very disappointing, even wil better suitable LED bulbs. More info and comparison here: https://retrofitlab.com/blogs/news/h1-led-versus-xenon-mini-h1-projector3. Using a Bi-LED projector vs a Bi-xenon projector.The Bi-LED projectors are designed around the LED's and have a good output and pattern. That said, based on output and pattern, the premium HID/Xenon (Ultimo projector with XB bulbs, EvoX-r 2.0 with Osram bulbs for example) usually offer a better pattern/output. So, in short, LED offers big advantages in terms of installation, less parts that can break, no need to change bulbs, instant on etc. but purely based on light output and pattern, the premium HID/xenon equivalents usually perform a bit better.