Long War 2 infiltration?

I'm looking for help regarding the Long War 2 mod. When 'infiltrating' a mission, you get more progress with fewer squad members, equipped with SMGs and 'other stealth-ish items' (which I don't have as I just started using this mod)

Can a group of 4-5 'infiltrators' succeed if the mission get ~150% progress, or should I just bring my best squad and try with ~60%? Because I thought you were supposed to send in infiltrators, and then swap them out for a proper team, but as I found out, that's not the case.