Box work at home

I brought one of the flyball boxes home with me on Sunday after the tournament. I had both dogs on it today for two short sessions each. Monty is a pain and will 4 paw turn on it when training at home and doing boxwork at team training but won't do it when he's racing.
Storm does great turns but only with the hurdle in front to encourage him to jump onto the box. He'll only do 2 paws if there's nothing in front of the box. The hurdle will always be in until he's actually in races so that he only ever does proper turns and doesn't practise 'bad box technique'. He's really quick on the box and is on-off like lightning. Monty was trying to dig for England through the window on the door while Storm was training lol.