I Have...
...A Lux Diamond Jubilee, presently in storage, that will be coming up in the Spring. You will look a long time to find a vacuum with better suction. Vacuumfreeke is right about the PN noise; Lux didn't seem to put much effort into making quiet ones for a long time. Both my Diamond Jubilee and my L are "blessed" with noisy ones, and yes, they've had the attention they needed with bearings and brushrolls and belts and whatnot.
One tip about your Lux's hose; if you can swing it, it's a good idea to get a new hose for "go" and keep that irreplaceable woven hose for "show." Its rubber carcass (underneath that woven covering) will crack and split if you use it, making it leak air. Those hoses are now more than 25 years old (the Diamond Jubilee was Lux's 1984 model), so they can't hold up much longer. There is a method of fixing cracked ones with liquid latex, though; you can search the archives at Vacuumland for more info. What I did was to buy a new Aerus replacement hose for use, keeping the original for show.
The Miracle Mate is a Compact/TriStar clone, using the same "cyclonic" principle and the same bag system. I have not personally used one, but I do own a TriStar CXL, and it's a terrific vac, my favourite in fact. A pic is below.
Sounds like you had a great afternoon's thrifting, mister! Congratulations.
