A little more info and some speculation
I should note that Lesinutah is correct that Powr-Flite was originally a parts supplier that turned into a manufacturing company, they were originally known as Southwest. When exactly they became affiliated with Tacony, I'm not exactly sure, but while Tacony's residential stuff, Simplicity/Riccar, is generally well regarded around here, it is of my opinion as a service tech in the janitorial/carpet cleaning end of things that between the stuff that they source and stuff that they actually build, Powr-Flite is absolute junk with few exceptions. Parts are also far more difficult to look up, source and cost more than those from actual commercial companies like Nilfisk-Advance that build quality equipment. A year ago I worked on a Powr-Flite automatic floor scrubber and despite a fresh pad, new squeegees that were properly adjusted and good detergent it just would not clean well at all; it was as though it had all the ingredients of a scrubber but somehow it just didn't turn out right. As my old boss at Michigan Maintenance used to say about them, "Powr-Flite, Powr-Fright, don't break on me tonight!"
Another company affiliated with Tacony is Tornado Industries, who at one point were an independent company and then were owned by Karcher for some time.
Regarding some changes made during the Bissell Sanitaire transition, the mold for the looped handle already existed, it was already on the higher end machines such as the SC889 and S677/S675, also the Gray power cord lives on on the cheaper models such as the SL635, the SC679(which used to be called the "Maid Saver" due to its light weight) and the SC684. Now that they have access to the Bissell bagless units based on the old cleanview and others I wish the long trotted out commercial version of the old Eureka Whirlwind would go away with its awful filter in bin clog-o-matic nature. Unfortunately, Bissell has kept it on even longer. They also still make a Sanitaire version of the 1980s Eureka Ultra in the form of the Duralite, which is decent and should run circles around an Oreck.
About the new motors, I've still yet to find any good reason why most people here hate them. The seem to be just as long lasting as the old ones and just as serviceable(Eureka motors have always been difficult to do more than change the carbon brushes), though at the very beginning of the run they did epoxy the screws. The only scenario where they aren't as good is in event of a blown fan, if the user continues to run one of them with an off balance fan for extended periods it will destroy the motor as the lower bearing support is not as thick as on the older motor. On the old motors they were a little more tolerant of that specific abuse, but eventually it would still destroy the lower bearing anyway.
To the speculation, Eureka made their own motors up into the 2000s, then at some point it appears that they sold the original tooling to Ametek Lamb who continued to supply them to Eureka for a while, at some point I guess they decided to have another company make it for them and since they were no longer tied to the legacy tooling they took the liberty to make some changes, namely make the top of the motor out of one piece of thermoset plastic instead of having an separate steel bearing retainer screwed to the top which is what gives old Sanitaires their distinctive sound. Without their only buyer for that motor I'm guessing Ametek sold the tooling to whoever is currently making the motors for Perfect.
