I owned a Miele Teiflex. Very powerful.
Terrible engineering (which is shocking considering their history) of where the roller's bearing met up with the plastic of the head.
Hair would really tangle up in it. I constantly had to take the head apart and was always so ready to do it, I kept the specific star bits in a zip lock, so I wouldn't have to search for them.
I even bought it from a mom and pop store in DSM, they gave me a free head because it kept happening......and it still happened.
Moved onto a Shark which has somehow absolutely performed better in regards to hair.