I've never heard of Trupanion before now, but back in May of this year, I did some extensive research on pet insurance. I have a 14-year-old cat who is pretty much at the outer edge of being covered by ANY of the "top" companies out there.
I'd mostly try to Google around for reviews of a certain company, and try to parse out the shill reviews that may have been written by employees of the company itself (I saw a remarkable amount of those, with every company I looked at).
I personally chose Pets Best because it had the most options for me (I could choose my deductible, coverage amount, plan type, etc.). I paid $603 for an entire year of coverage at 90% reimbursement, with a $200 deductible.
So, you could get a quote for Danna at Trupanion and compare to my experience, or get a bunch of different quotes :}