I've had this insurance for many years, maybe 7 years now. A vet told me way back then to buy pet insurance and keep paying on it even though I wouldn't have any claims for several years. She said eventually I'd need it and it would make all the difference in keeping my dogs healthy and alive for a long time.
This year, I had claims on 2 of my dogs. One has arthritis in her knees and an enlarged heart. The other has arthritis in her spine. I was devastated to hear the results of the Xrays, knowing that there would be more treatments and possibly tests, but I had the insurance in place their whole lives and submitted the claims for the first round of tests, $775. per dog. My claims were paid in about a week and there's a huge weight lifted off of me knowing that I will be able to continue with anything needed for them without going into major debt.
I will say that I have paid out a lot to insurance for 4 dogs over the years. My rates have gone up a lot, but the insurance also started covering a lot of additional things that it didn't cover when I first bought it. I shopped around recently when my policy was up for renewal and found that Pets Best was still the cheapest for full coverage.
I bought illness and accident insurance, although I was mainly bought it for fear of accidents. If I only had the accident insurance, these diagnosis would not be covered. Therefore, I strongly recommend buying the illness coverage, too. No matter how good we take care of our pets, we really don't know what they went through before we had them or what types of things they are subject to from their heritage.