Yellow and green turn off lights are available at all ( I think) airports that host low vis. ops and maybe lots that don't and very usefull they are too, assuming the assistant working the panel doesn't try to get smart and turn a set off that you aiming for coz. HE thinks you aren't going to make it, it's happened to me a few times now.
The switched taxi light system at LHR is another matter and in my opinion is more trouble than it's worth and slows things up. You seem to be stopping and starting all the time at night waiting for a route to light up because the stop bar can't be dropped till the other aircraft is past it's next block. Like I said, great in 75m vis. but just not needed at other times as all other airports prove on a nightly basis. Is it going to be installed in the new tower?.