I don't just use it for spot cleaning. I do my complete breakdown cleaning with Virosan/Nolvasan about every 2-3 months. No need to use the bleach solution - it's just as effective and is recognized as a safe alternative disinectant. A bottle of bleach is just much cheaper (I can get them for under $1), so it may be much more cost effective for a vet to use that for major disinfecting.