When you buy any used boat, assume you are intending to get a good survey done - worth paying for the best which could include checking the keel security. Regarding Keels falling off, there are some fact surrounding this, but there is far more nonsense and invention. Have a look on ybw forums and do a search on Bavaria keels - there is a fair bit about it. It is worth reading all the posts though and you will begin to pick up some genuine facts. In truth, keels have come many different makes of sailing boat over the years in many different circumstances, not just Bav. In the case of Bavaria, the anti-AWB lot enjoy using it as an ongoing worn out joke, regardless of facts!