Oh that sounds like a quick little pony then. I just adopted a 16.3 hand thoroughbred, Bayberry, this past saturday from a rescue and he's not speedy, but he takes up ground! He has about a 12-13 foot stride at the canter. We're taking him to a hunter/jumper show this sunday and doing 2 foot 6 inches. Hopefully he'll be ready. He doesnt like the little jumps but he's never ever been to a show, besides his harness racing when he was a baby. Hopefully he'll be good!
Your two ponies though look very good at jumping though, they seem to love what they do!!