I do it, when I vaccinate. My dogs are all seen by my vet yearly anyway--usually for one reason or another. It's a third of the price for me to do it.

However, I have recently changed my vaccination schedule adn will be going to once every three years--since they legally have to have a rabies shot that often, I'll just have the vet do all of them at the same time. I'm actually thinking of just paying to have him come out here, instead of 21 app'ts!