I adopted a puppy from the local Humane Society and looked into getting some pet insurance for her after we had a few minor puppy incidents. When I initially signed up, they hit us with a pre-existing condition of a heart murmur (even though it was on ONE vet note and it was when she was severely dehydrated) and several temporary conditions, which if they are seen again in 12 months, will be considered pre-existing. So, this was everything all puppies go through: parasites, diarrhea, vomiting, vaginitis, etc. Now, if our PUPPY gets one of these illnesses in the next 12 months, they won't cover anything related to those. In addition, I have since submitted three claims and had to follow-up on each claim because I either did not agree, or they claimed to not get the information from my vet. When I contested that the heart murmur was a pre-existing condition, they never got back to me until I followed up over a month later over the phone.
I will be fair and say the few positives I have had are that customer service has been friendly and helpful and that submitting the claim is easy if you do it via email yourself. However, if you are paying a monthly fee and getting nothing covered, this is not nearly enough for me to stay with a company.