Steve,
I've talked to Paul at Williams about them. They have a pair fitted to a Landrover and at night the dip beam is brighter and more defined than the standard 7" units. Main beam is quoted as "awesome".
I also asked about compatibility with the bulb failure warning system on the Plus 8 and new +4: it seems they don't trigger a warning.
They look, in my view, rather good. Cheaper than a new Aero 8....but still about £650 the pair.
