Kevin:
I am sorry it took so long to write back but I haven't checked this thread in a while... Electrolux didn't use to have many models at one time. As far as I know, there usually was only one unit. They did produce a bare bones model called the T which was not very successful. I forget which model it was sold alongside and what year. Starting in the 1960's they began to offer different features for more money. For example, my mom had a Model R with NO cordwinder, but my grandmother had a Model R WITH a cordwinder. So product differentiation was in motion. The Hospital G before that was a special model with a special filter designed for "health" reasons. Flash forward to 1968 and the 1205. They sold the 1205, albeit with different names and numbers, through the 70's with the Golden J, Super J, Olympia, Diamond J, Silverado, Marquis, Grand Marquis, and Ultralux until about the late 1980's to early 1990's. During this time they also introduced "special" models of the Olympia, Silverado, and perhaps one more. These did not have any features such as shut off, bag light, etc., and no cordwinders. Beginning in 1984 or so they introduced the first plastic bodied machine to judge the public's response. It was the Hi-Tech 2100. It was basically a 1205 with a lexan body and different lights and with a dial on top. They had to convince the public it would hold up like a metal machine. They were planning on phasing out metal body machines and the 2100 was the start. They sold these alongside each other for several years with the Silverado, etc. metals. Along the way, changes to the power nozzle came along at different periods, often appearing on a machine later in it's production. The Marquis, Grand Marquis, and Ultralux were the last metal body canisters. The design of the 2100 continued on with the Diplomat, Epic 6500, Epic 6500SR. At some point they took away the dial, lights, and automatic technology and made it the Ambassador (I, II, III) and it became the low tier model. Shortly after 1990 the metal canisters ended and the Renaissance came out, thus ending the run of the 1205 as the high tier model. The 1205 continued on as a plastic body under different names and with varying degrees of technology as the reborn 2100, reborn Ultralux, Classic, etc. For example, in the late 1980's they sold in the mall near me. They had the Ultralux, Epic 6500SR, Ambassador, and Diplomat at the same time. Some were discontinued he told us. They sold discontinued vacuums until they were gone. If they couldn't get you to buy the Renaissance, they would sell you an Ambassador. They sold a few of these on QVC but I'm not sure which ones. They had a very different upright sold on TV that looked WAY different than any you've ever seen. Bottom line, all metals with increasing amounts of plastic from beginning to 1980's, then no metals made after the last Ultralux. The Renaissance was sold alongside the Ambassador (perhaps different name) and the Epic 6500SR. I'm not sure when the Epic 6500SR was renamed the Legacy but it is one of the few machines to not have been changed much since introduction. Only the power nozzle is differently shaped. The Ren continued until the introduction of the Guardian Ultra. Hope this helps understand the continuity.