They're fine for washing 'smalls' and perhaps one pair of jeans. But not more.
So bedding and towels - no.
Folks expect more nowadays
If you clicked the ebay link you would see that infact the capacity is 3.5kgs (about half of a normal domestic auto washing machine). It will not 'do' quilts but we have had no problem with bedding or a combination of clothing.
Yesterday did 7 days worth of washing produced by 5 people (4 adults + a 9 year old) It did take 8 loads but it would have taken 3 or 4 loads at home in the full size 'auto'.
They are not 'toys'