I just upgraded to Sylvania Silverstar headlites and they are 1000 times brighter than the stock yellowish ones. $50.00 for a pair of headlites but it was worth it and they just plug right in.
The H-4's plug right in too, but it's recommended to wire in relays so you don't have a high amperage draw running inside the car and through the headlight switch. I wondered how much those Sylvania bulbs pull? But they throw some nice light, huh?
They might be a viable alternative to cutting into my new harness to add relays.... :-k