I was going to get the Cibies, but then I stumbled across the Silvania Xenarc (HID) headlight replacements.
I heard bad things about them (light pattern), but these are supposed to be the 2nd-generation of them. Not sure if they still suck or not, and they are $$$, with high-beam HID's as well (I don't like that).
Maybe I should just stick with the halogens...
I would for two reasons.
1. The standard Cibies in my 62 work great, better than most new cars including my F-150 which has excellent headlights.
2. The HID in a compromised design (Modern HID's, like my old Jetta, were huge and had very intricate reflectors, my Jetta's HID's were amazing though). The cutoff never bothered oncoming motorists. In the 165mm design, I bet you would have a lot of stray light.
My 2009.5 Pontiac G8 GXP has non HID Projector headlights. Many of the G8 guys are putting HID upgrades in them and getting good results. I don't understand it as Utah has some VERY dark roads and I have never had issues.
That is my 2 cents. I do not believe my 62 will ever need more lighting towards the front than I have now.