I may be biased towards the Danger Room uniques, but this Mystique looks like an amazing tie-up piece. Double roll-outs while only taking one damage from attacks if she rolls bad, combined with Precision Strike for a budget price sounds nice to me. Her death trait is pretty annoying though if you're running her with others that use Shape Change, especially if that's their only way to avoid damage. In my playtesting though this comes up more on Robot teams than it does on Brotherhood teams, not that it makes it any less punishing when it does pop up.
Thematic Dial: 8/10,
Viability: 8/10,
Fun Factor: 8.5/10, fairly balanced figure

This is a great option to have in your sideline for Mimic (at 45 points) to copy. Plasticity, super senses, shape change, toughness AND a stop click make for a tie-up nightmare!

I do agree with you Adam that she would be good for Mimic, but he wouldn't get the pseudo-stop clicks the danger room figures get. He only gets to copy standard powers, and the "stop" clicks are tied to a trait.