Don't bother. I went through the process of trying pretty much every available 'bulb' in mine about 5 years ago.
Halogen bulbs work well in reflector lights, but the small reflectors and light shifting lenses in any projector lights robs too much performance from them. Even the 'best' halogen bulbs in them were barely any better than H4s on dipped beam. Projectors need a stronger, 360 degree light source, which is why HIDs work really well. They produce light which evenly fills the reflector (like a halogen bulb), whereas most LEDs have diodes on opposing side to each other. This means the reflector isn't evenly filled and shadowing can occur. Twenty20 make a LED bulb specifically for projectors. A fella I know fitted some in the aftermarket headlights in his Caddy and they are superb.