English staff vs Amstaff

Has anyone had Staffordshire bull terrier and an American Staffordshire terrier? I'm wondering what the difference in personality and nature is between the two dogs and also if one is generally more intelligent?
Answers preferred from people with experience of both dogs please.

I have some experience but not with the two together. AmStaffs are bigger than a traditional Staffordshire but to be honest, that's the only real difference.

A friend of mine has an AmStaff in the USA where I've spent a good amount of time and their Son has an AmStaff. They all think he's really smart (the dog not the son) and loyal and very well behaved in and out of the house. I do tend to roll my eyes at this knowing that the history of the breed goes back to our original Staffy and therefore should share similar traits.

Having only known one AmStaff I wouldn't like to say either is more intelligent.