I love VPI! I hesitated getting pet insurance, but my sister's dog needed an expensive operation and that settled my decision. So we insured our miniature schnauzer right from 14 weeks.
They have been very easy to work with. When you apply, you mail in your vet records so they can rule out any preexisting conditions. The only thing they ruled out for us is food allergy related problems.
We've already submitted a few claims and got one back in under 3 weeks. They have been wonderful to work with and the process is very easy.