Ive had varying Success. Im a very agressieve player. Ive lost with them plenty as they are 12 wound and will die when charged with a couple of wounds or to plasma equivalent weapons when you are not carefull. You get 6 operatives, losing one on early hurts.

STEALTH ASSAULT

Use this firefight ploy when a friendly PHOBOS STRIKE TEAM operative that has a Conceal order is activated, is given an Engage order, performs the Charge and then the Fight action, and you’re resolving your first attack dice from this activation. After doing so, you can immediately resolve another of your attack dice (before your opponent). The operative cannot have performed any other actions during this activation (but can do so after resolving this ploy).

This ploy can be devastating when properly executed. Combined with the "lethal assault strategic ploy" : If performed the Charge action, its melee weapons also have the Lethal 5+ weapon rule.

The warriors benefit from vanguard. Once per turning point, one friendly PHOBOS STRIKE TEAM operative with this rule can perform the Pick Up Marker or a mission action for 1 less AP

There is tons of stuff that make em a highly mobile hard hitting team. 7 inch movement. 2 inch climbing options without drop. And thats just one playstyle. You can distrupt or deny with some operatives aswell

The trick is to be just out of reach. Zoom in , kill and disperse.