As far as headlamps are concerned, if the one you have is lacking, there is very little wrong with the original, if you have it. You will have to find a set of 'ears' to mount it though.
Depends on the 'look' that you want.
I am using the original on mine as it still suited the 60's cafe racer look that I was after, I mounted using a set of aluminium ears. This setup seems to be able to attract 'flying critters' at night with great efficiency (have to keep my mouth shut in summer). I can see a great distance with it, now it sports a halogen bulb thingy...
The mounts that I use are from here:
<http://www.discovolantemoto.co.uk/index.jsp
Cheers
Steve H