First of all, for the sake of EVERYONE in the car hobby, do NOT do an HID conversion of any non-HID light. This kind of irresponsible behaviour is what draws unwanted attention from LEOs to us - and in this case for good reason. The NHTSA is investigating now.
Between Cibié and Hella, the debate rages on. Compared with anything else, they are light years better (please forgive the lighting pun), but if you are trying to get all that you can from incandescents, then Cibié lights should get then near-$100.00 nod. Definitely add a set of relays to get the voltage to the best it can be (and don't forget to actually measure it - some regulators are very different from others and rob the system of EMF).
Personally, I prefer 80/100s with CLEAR globe. Incandescents of any kind - even halogen filled - emit longer wavelength than full spectrum (i.e. red shift). The nonsense of blue tint "correcting" them is pure fallacy. You can not add colour, you can only subtract by filtering, and blue tinting filters out some red to give the APPEARANCE of white - but now you have a spectrum missing some red and some blue. You can not see at night what you do not reflect back, so if you don't send those wavelengths out, you don't get that part of the image back.
Before you feel too bad about spending $300 for lights, bulbs and relays, and remembering that in the USA, those extremely good H4s are actually not legal (but nobody will likely ever call you on that if you don't do anything stupid - such as convert to HID or not aim carefully), consider that the next step in getting fully DOT legal and full spectrum white 5 x 7 headlamps are LEDs - that will set you back over a grand a pair. But, GEEZ, are they sweet.