for me a couple of years back it was new Cibie headlight. made out of proper metal and glass with a decent reflector rather than the miserable plastic stock globe, that also was burnt where the H4 bulb fits in. a Hella globe would just be as good,
then I bought a relay kit from
http://www.easternbeaver.com/Main/main.html so that the volts go direct from the battery to the light bulb rather than through the Hi-Lo beam switch and the existing pathetically thin wires. now the switch just operates the relays to flick from Hi to Lo beams. made a tremendous difference. I measured the voltage drop through the switch before fitting the relays and from memory it was about 1.5 V due to the resistance of the thin wires and the switch. that equates to a lot of Lumens lost. now with the wire direct from battery the voltage drop is next to nothing
with all of this, if I inadvertantly leave the Hi beams on even during daylight hours, oncoming cars crack the shits and flash there lights at me and thats still with the stock bulb.
next I'll get one of those Philips X-treme vision bulbs as above
the LED's maybe bright, but with correct wiring, a good reflector(globe) and halogen bulb I think this gives more oomph
