We signed up for Trupanion in July or August and twice have filed claims: once for an ER visit and once for a vet (sick) visit. They don't pay for well visits or the exam fees, but they do pay 90% of the sick visit procedures. My last bill was $187 and change and I just got a check for $125 and change.
I like this plan a lot because we can budget for the well visits... it's the little surprises along the way that get us!
It is also super-easy to use. You just give the doctor the Trupanion form and then next thing you know Trupanion is eMailing you to tell you that your claim is being processed.. and then again to tell you how much you are getting back. It is very fast (12/16 visit date, 12/23 check issue date)!