Wish I could produce BW pantographs as good as those.
What I meant to say is that it is apparently very hard for the manufacturers to (affordably?) mass produce a well detailed, working (sprung and/or current collecting) OO scale BW pantograph.
Hornby have said their Class 87 will not feature one, the Bachmann Class 90 - sounds like it should be very good if they are going to the trouble of putting in a servo motor - however my guess is the link wire from the motor is serving the job of holding the pan against the wire, instead of a spring. As for DJM Models' Class 92, Dave so far seems a little coy about providing details in his thread.
It seems to me that it would be easier if the model manufacturers approached the locomotive manufacturers and ask them to design pantographs that in future are easier to model and to mothball the BW pan!