I don't currently insure my horses, but I have in the past. A friend of mine does insure - Thank goodness, as she has used the medical portion a number of times.
Mine are insured. They have mortality and major medical (Mags) and mortality and surgical (Havoc). Even the big mare is insured, mortality and surgical, but who knows if they'll pay out when we have to put her down because of her feet.
A couple years ago, when Snip was in for the laminitis and Mags was in for colic, I didn't even bother claiming Mags because, quite frankly, we were busy trying to keep the other girl alive, and you only have 30 days.
Some of ours are insured...when Nuke had emergency colic surgery two years ago the Major Medical insurance was wonderful. It covered a large portion of his $17,000 surgical/ICU costs, and the payout was made within 2 weeks of submission of the claim. When my gelding broke his hip both the emergency treatment/diagnosis were covered, as well as the follow-up treatment, and again I was paid within weeks of submitting the claim.
However, I personally know of mortality claims made which were NOT honoured, at least not in full, by the insurance companies. I don't know about the rest of you, but I have a huge problem with insurers agreeing with owners on valuations of horses, collecting premiums based on those valuations, and then choosing to pay out only a portion of that valuation amount. It's happened in more than one case here in BC, with the result that a number of us have chosen to insure for a much lower mortality valuation than the actual replacement value of the horse, as that's all we're likely to receive, and therefore all we're prepared to pay premiums against.
My show horse was insured but my "pet" horse could not get insurance because of her age. I was happy to have the insurance on my show horse when he got poked in the eye with a piece of hay on the trailer and ended up spending a month in the hospital to clear up the infection. The $10,000 bill was completely covered by his major medical policy.