For the sake of giving a short answer, I recommend having at least one fighter capable of challenging armor focused fighters, and BMF being able to disable Blockbusters as well makes her pretty good at it. She does compete with Headstrong, but Headstrong needs her MA to do control meter and can't bleed as well if you need that for any reason, and has command grabs in return. If you already have someone who can armor break well, no need to invest in her right away (but keep her around, as if/when you start playing rifts she's a good answer to many of the stronger catalysts imo).