We've been very happy with Northside Animal Hospital on Sherman Ave. The prices are very reasonable. I believe we got a "discount" for taking both of our cats in at the same time. We were only charged for one office visit, anyway.
Shortly before Christmas, one of our cats got sick from something and they were able to see him 15 minutes after I called. And they split the bill so that we didn't have to pay the whole thing at one time. He had to stay overnight and have a lot of tests run, so that was a bit expensive.