This ally is great. She is very hard not to include in most of my justice decks.
On their own neither Monica Chang or Surveillance Team are good value. But getting a free Surveillance Team with an extra snooper turns her into a great value card. You're essentially getting 5 thwart (over a minimum of 4 rounds albeit) and a chump block for 3 cost. What's not to love?
I usually run her with just a single Surveillance Team and just ensure I've cycled the snoopers before I reshuffle my discard pile.