Sid (the more pitbull looking one with the shorter ears) is the more independent of the two when he and Simon are together but the least confident when they are apart.  He is a rambunctuous puppy and I anticipate him being the more active of the two.  He also has the most personality.   He also loves to carry around the treat dispenser ball.  It's bigger than he is so he holds it by the opening and above his head, running almost on his tip toes.  It's hilarious.  He's receptive to correction and minds better than any Chessie I've ever had, though.  ;-p 
 
Simon (the one with the bigger, floppier ears) is a confident puppy but is more middle of the road than Sid.  He settles down better and is more willing to be held and cuddled.  He's a social boy and runs up to new people and dogs although was definitely not super comfortable when he was being held by 20 complete strangers at Fashion Island.  He warmed up more with each new person. 
 
They both love wrestling and playing tug with Bernie and they are both very smart.  We have company coming over this weekend with their dogs and a birthday party they get to go to so they'll have more socialization with people and dogs. Oh, and they love water too! Here's Simon in the pool: