Does anyone know when Eureka went from 4 digit model numbers to 3? I have my mom's which is similar but maybe from 1983-ish, model 1942. It has a darker gray hood, with white trim and has a rugulator instead of the dial-a-nap, and does have the vibra-groomer II. I remember when I went to shop for it, I had an ESP at the time that I loved, but she only had two carpeted rooms, so I bought the 5.5 model, and I don't notice that big of difference in performance from the ESP model. Hers came with kind of a squarish plastic handle which I hated, so found a chrome Sanitaire handle with a white grip at a friends vac shop, so it has a much better feel to it. I also had him change the cord out to a longer cord, and my friend Philip(Kirbyvertibles) gave me a conversion tube for the bag so I can use the Sanitaire ST hepa bags in it. The outer bag is really attractive but just vinyl, so the hepa bags fit the bill for good filtration. It's a pleasure to use and I don't think there's a scratch on it. Poor mom never knew what upright she would find in her closet, as I wheeled and dealed vacs back then, but I was warned to never to sell her pink GE canister, or the fur would fly!