Yeh i will be monitoring things very very carefully.  The dogs have almost tripled in size over the past 3 weeks/month.

It was exactly the same behaviour I have seen when taking dogs pig hunting, once they latch on, they just wont let go and shake their heads side to side violently. I was completely shocked this afternoon because there were a few adults in the backyard and the dogs still had a big go with no notice or reason whatsoever...

Might contact a staffy dog website/forum and get some advice from a few experts. I am sure some will say that they can be trained properly, and some will say the opposite. Time to make some serious enquiries.

I can put you onto the biggest/best dog forum in the country. Full of experienced breeders, with all the knowledge you need. I do think training of any pup should start from day one. I'd be booking them into puppy pre school ASAP and make a start with the training. The longer you leave it, the harder it is.

For example, the biting and attacking of your ankles the other week should've been stopped right there and then.

I can find out the best trainer in your area too if you need any advice or questions now or in the near future. I wouldn't throw the towel in just yet and get rid of the dogs.

ETA...Have you contacted the breeder you bought the dogs from ? What are their thoughts on the matter ? Their response will tell you a lot about them. If it's a short, don't really care answer, you know their not dedicated to the breed and just out for a buck.