Size
The Rottweiler is far larger: about 45 kg (99 lb) as an adult, against 14 kg (31 lb) for the Staffordshire Bull Terrier.
Lifespan
In UK vet records the Staffordshire Bull Terrier lives longer: a median of 12 years, against 10.6 for the Rottweiler.
Shedding
Their coats shed differently: the Rottweiler moults most as the seasons change, the Staffordshire Bull Terrier sheds through the year.
Grooming
The Rottweiler needs more grooming, brushing a few times a week, where the Staffordshire Bull Terrier needs a brush once a week.
Temperament
They differ most on loyalty (Rottweiler: sticks close to its people; Staffordshire Bull Terrier: bonded to its family) and on handler demand (Rottweiler: needs an experienced owner; Staffordshire Bull Terrier: needs steady training).
Alike
Both are rated the same on affection: a lap or leaning dog.