The Camel was a tough mount to master with any engine, but I would surmise that the more power it had the more difficult it was to handle. So, that the Clerget and Bentley mounts would have been the most difficult of all. I suggest that you look at
http://www.aviation-magazine.com/sopwith/l...ml. The author opines that the Camel killed more Brits than it did Germans.