Time for me to stick my ore in once again lol.
The Sebo Felix is certainly designed for hardfloors. As well as the array of combination attachments such as the combi, you have the parquet nozzle, but also the Disco head, which polishes and vacuums at the same time, and it really does work, I have seen one in action.
Also, I really, really can not see how the felix is "terrible" at deep pile carpet cleaning. There are hundreds of vacuums which do a genuinely piss poor job of deep cleaning dense piled carpeting. Right, so the felix is no Kirby, probably doesn't deep clean as well but there are not many vacuums that matches the felix. The Felix cleans every bit as well, in my opinion better than a Miele S7, which used to bunny hop over my hall carpets, not digging in far enough.
The bristles the PT1 powerhead whatever it is called, the one use don the felix and the newest canisters from sebo have stiff, long bristles coupled with a 175 watt motor to spin it.
But again, it may be beyond the whole "its not a Kirby " excuse, but looking at the bigger picture, it may be a patriotism problem; the Sebo is of course German, not American. So we can't like it too much. Although that might go for a lot of US customers, but then again there is nothing wrong with buying home grown products, in-fact it is admirable, but the British for one, and probably most Europeans would rather buy a good product and not care where it is from.