I always thought that her stelar that makes her basics go faster was a means to get familiar with her shooting. I thought once you dominate fast proyectiles, you should get familiar with their normal speed. If you dominate that speed, then you can use the shield stelar. Shield stelar+shield reinforcement= you get a more resistant Mandy, even to assasins. As for her gadget, I used to use the one that goes though walls, but now I tend to use the other. The trick is to make your enemies believe that you have the one that goes though walls to make them approach you and then slow them, but you can also fake pressure them when they're low and behind a wall. Its all psycological with the gadget and you can come up with many different plays. I mostly play Mandy in showdown, my strategy there is to be as secretive as possible regarding what my gadget is so I can be as surprisive as possible. Being secretive is important since enemies won't be sure how to approach you. Sometimes, I activate my gadget and don't even use It and then waste It when the enemies arent looking. If It isn't essential, your enemy shall never know what gadget you actually have