What an amazing thread; five pages of detailed replies and thoughtful responses. Wow. I'm impressed and awed.
(And what am I doing on an overcast Wednesday afternoon, reading a thread about vacuum cleaners, instead of addressing the detailed stuff I am supposed to attend to? Sigh. It is the endless temptation of reading about technical stuff, and the sheer joy - unrelated to any external necessity - of adding yet further layers of information and knowledge to already disturbingly well stocked memory banks. You know, it is a real pleasure to meet, and converse with, so many nerds, and I mean that in the sincerest way possible).
Anyway, back on topic, when I was a kid, we had the old classic 'Hoovers'. Now, a small, nifty, powerful little Miele (S2110) does the job; we've had it a good few years, and it has never given us any problems.