When I went to the CP Spring Fayre at the weekend, I was told about a little girl, about 1 year old, who had been brought in as a stray, and tested FIV+ on the in-house vet test.
Well, I'm pleased to say that the Glasgow test has proved it to be a false positive, so it just goes to show that the in-house ones are not always reliable, and should always be backed up with a lab test if testing positive.