I did both high and low beam on my ST4S and they worked perfectly.
I brought my kit from autolamps-online, and wrote fitting instructions too.
They aren't cheap from them, but the owner worked for philips lamps, so knows his stuff, and his lamps are manufatured by philips now so are correctly focused, regardless of base type.
I did fit them to my 996 before the ST4S, but didn't write instructions, and that is a long time ago now too, so b allast / ignitor technology has moved on.
Chris, ask me about it on Saturday
