If you're referring to the "Extra Mafia Members" which cost 20 Reward Points from the Godfather, they do not have applicable stats in fights in and of themselves. However, they do act like normal player mafia members, increasing your mob size and equipping a weapon, an armour and a vehicle which in turn will increase your effectiveness in fights.
Thus instead of blowing 25 Reward Points on a single fancy item, you usually get better mileage by boosting your mob size... Of course, if you have the time and drive you can just try to recruit players into your mob, saving the points for something else. =)
Once purchased, you can see the amount of these extra members at the very bottom of "My Mafia" page, where they are listed as "Hired Guns".
To the Asker from Nick: I apologize for the faulty answer. The above answer is correct.