I am writing an article for a yachting mag about pivoting keel cruisers; both where the whole keel pivots or a centreplate pivots up inside an external stub keel. I am looking for opinions on the various methods used; especially continuous 'worm drives' operated manually. I am also interested in hydraulic methods. I have read a few French 'forum' features which speak of difficulty getting at these things if/when they go wrong and also difficulty in getting spares; especially on old models. Have any UK owners got opinions/advice? I have about ten days to copy date! Many thanks.