Mechanical Stokers

Does anyone have any experience of Mechanical Stokers on a Bulleid Pacific?? I know that 35005 'Canadian Pacific' (Yes my favourite loco) had one, but were there any others?
How did they work and were they only used in testing and what speeds etc were timed?
Alot of questions I could ask regarding these....

Some Information on the Mechanical Stoker as put on 35005;
"Mechanical Stoker, 3115

In October 1947 Bulleid had obtained a reconditioned Berkley Mechanical Stoker in Canada that was fitted to s21C5 Canadian Pacific in March 1948, at the cost of some coal and water space. To offset the loss of water capacity the tank was raised by 14 in, and four rung ladders were fitted. The stoker was driven by an auxiliary steam engine and had a three section helical conveyer screw that moved the coal from the tender to the firebox. As this required smaller, uniform coal a coal crusher was provided but this created a lot of dust which was only partly contained by installing a canvas cover to the bunker. The experiment concluded in April 1951 but the tender was not restored to its former state and was eventually, in May 1959, rebodied with the 5,250 gallon tank."