burton boards have a 3 hole pattern instead of the usual 4. burton bindings come with base plates for either and i dont know if flow does aswell. you can use flow bindings on a burton board but you will need to get the correct base plate that fits the three screw pattern. if the bindings dont come with both sets, go to your local board shop and they should be able to hook you up no problem. shouldnt cost much, probably like 10 bucks? they might even give them for free if they are cool.
OR if you have friends with burton binding using non burton boards, they probably have an extra set you could take off their hands!