I have had a lifelong aversion to cylinders for no other reason than my mum never had one!
Thankfully I am now cured.
Henry is NOT back breaking however. He is very lightweight and portable.
Think about it. With an upright you push the WHOLE THING back and forward at each stroke, including the motor which is the heaviest part. WIth Henry you are only pushing the hose back and forward. He works equally well on carpets, wood, lino, slate, and any other surface. My BIL is a builder and he says builders swear by them because they get knocked around building sites and used to suck up rubble and seem indestructible.
I really don't have a bad word to say about Henry. My kids (5,4, and 2) all want to do the hoovering because of his face. (we don't get out much). You can detatch a section of the hose so it is the right size for a toddler. My kids now do most of the hoovering for me.
The flex is so long I plug him into the hall socket and can vacuum the whole house without replugging.
He rolls on castors , it is really no trouble.
Good grief I am calling it "he". Must lie down in a darkened room.
I have not had personal experience of the mielle cat and dog but have heard nothing but praise for it, both here and on consumer websites.