If you upgrade to halogens, make sure you use the adapters for the wiring with the ceramic connectors. The standard connector will fit the H4 bulb, but it will be way too hot and you will damage your connector/wiring.

As others have mentioned, I upgraded to the H4/H1 set up, but I also added a relay kit to help eliminate the voltage drop to the lights. The drop in light output (lumens) is exponential with the drop in voltage. A relay kit insures you have full voltage at the lights. The stock set up has the power basically running from the junction post (battery/alternator power) through small wires into the headlight switch, then back to the lights. That's very inefficient. With a relay kit, the power goes right from the junction post to the lights. The switch just activates the coil on the relay.

I have a post somewhere on this when I did my conversion a few years ago. I went with the clear beams with the facets in the reflector behind the bulb for a more modern look, but there are plenty of housings out there with the facets in the lens to look like a stock sealed beam.