It's the best system in the world - and the safest. I don't operate out of LHR anymore and now when I'm taxying around some confusing mess of an airport such as beijing, I tell the other pilot about the fantastic system at LHR, they all seem to agree that it's what's need at all major airports.
Runway incursions are a hot topic at the moment. The LHR system has to be the best way of stopping them. Tell BA to get back in their box!