There is no defensible single price for every Shih Tzu. Obtain a quote using the correct breed, age and home ZIP code, then hold the annual limit, deductible and reimbursement percentage constant when you compare. Add the same optional benefits to each quote before calling one less expensive.
A puppy and an older dog can receive different offers even at the same address. The quoted premium also tells you nothing by itself about whether an existing eye problem is excluded. Keep premium and remaining coverage in separate columns.
To test affordability, write down the premium for a full policy year and the amount you could pay at the clinic before any reimbursement. A lower monthly amount is not useful if the deductible and your share of a large eligible bill would force you to decline care.