I've always gotten the longer-lasting ones for my cats.. then last summer my Sydney did develop a fibrosarcoma. Fortunately a surgical specialist was able to remove it completely.
But after that happened, mine get the one-year kind. (I'm not even sure about getting them rabies shots at all any more, after Sydney's tumor, since they are strictly inside cats.)
I've been Frosted (thanks, Elyse and Karen!).
I meant," said Ipslore bitterly, "what is there in this world that truly makes living worthwhile?"
Death thought about it.
"Cats," he said eventually. "Cats are nice."
-- Terry Pratchett, Sourcery