I've just renewed my insurance for contents, and once again it's cost me the best part of £1500 for a year's cover as a consequence of my watches (yes, I've shopped around, and no - nobody will do it cheaper). In addition, I've previously had to install (and keep professionally maintained) an alarm and a safe. I now find, both amusingly and annoyingly, that any watches that are high enough in value to be declared have to undergo periodic and documented "clasp and/or fastening inspections".
Given the substantial liability of servicing as well, I think I'm fast reaching the conclusion that the cost of ownership of a relatively valuable watch collection outweighs the benefits - unless, of course, you've been lucky enough to foster a relationship with "your AD" such that you can regularly get your hands on halo models to help balance the books (which I certainly can't). I think the next 12 months may see me bring the numbers/value down quite dramatically.