I've noticed that some members have modified D2S bulbs to use in place of D2R bulbs.

Is there any advantage to using D2S bulbs? Any color difference?

Also, as far as online searches go, I take it the only modification needed is to cut a new notch into the base of the D2S bulb. Other than that, the bulbs work perfectly. Is this correct?

 

All I know is that one is designed for a projector and the other is designed for a reflector-housing.