I have worked with cross guard sabers and your idea of a flow/cross guard would be epicly amazing if you could pull it off. While the cross guard can be used in all saber forms the idea of flow cross guard would be really challenging but not impossible. A few cons I can see/found: - You will have to relearn wrist rolls as the cross guard will hit your wrists and forearm, nothing more than teaching your body to twist the wrist more than usual. - Flow sabers are made for balance between hilt and blade, you notice hers has a very plain hilt, has no sound, also the thickness of the hilt is similar to the blade. The cross guard would change the balance so you would have to recalibrate the ratio and they are already hilt heavy however when you get balance it would be a matter of learning to get use to the weight. - Basic moves would like Fish Tail would be fine but when you are spinning the saber in the air or across your body for a Rocket or Angel Roll it may prove challenging or not possible as the cross guard could hit your body. However since its not been done before we wouldn't know till you tried it. Before buying the saber maybe see if you can't make one from pvc or dowel and use it as a lighter practice saber to help get the techniques/mechanics down. I am keen to see how far a flow cross guard can go :D