Having a sheddy dog...and sometimes a smelly one when he's got wet i have always noticed two things...
Henry with a turbo brush particually picks up the hair no problem...but...I don't know why but it becomes impregnated with the smell of the dog and TBH, quite smelly sometimes. I clean the filers, even the motor filter which is a faff to get to, put in hoover smelly discs, wash it regularly...it never really cures it.
We then got a Shark. Brilliant piece of kit, even better at picking up hairs ...but...same as above, it smells. The hoover smelly discs help more in the Shark than the Henry, but it doesnt cure it altogether. Also, the cord on the Shark is remarkably poor quality cable. Its not flexible in the winter, retains a memory and is a right nuisance to coil up( mind my house is kept quite cold, that doesnt help)
Years ago we had a compact Vax...but never suffered with the smell problem. I always wondered if its the way these machines generate their suction, suction being driven directly through the motor/fan or not perhaps.