Ok a quick run down this is only ime tho
They all have anti lemming built in so won't hurl themselves down stairs .
The can manage small lips / ledges up to about 1.5 cm .
You MUST move all cables but particularly thin ones like phone charges/ head phone wires , and laces , cat / kid / dog toys .
It seems like a lot of faff to start with but you soon learn to keep the floor clear and use cable ties where needed.
They cope with cat litter, dust fluff, hair , but not very long hair / fur.
You will still have to do your stairs.
They cope with ramps surprising well. ( 2 steps in to my kitchen ) a lump of wood does fine.
They are much quieter than a vac so fine to use early / late with out disturbing the neighbours .
Great for vac'ing the sofa under the cushions / mattress etc
Depending on hight space they will go under a lot of furniture, ( Eufy 11s will get under anything over 3.5 inches high.
So great for under beds , sofas , kick boards in kitchen etc.
If they do get stuck they will cry for help but cut out before doing any damage.
They need emptying roughly every 2 /3 days but it only takes a minute to do this .
You have to name them.
If you are in the house while they are running they will gently bump into you for affection.( 
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