Just as stated above, you may gain 1-3 WHP but, you won't feel 1-3 WHP and unless you are a hardcore track racer you have no need to do this...
Track racers do this for weight savings and better feel BUT, remember that their car starts one time and then never stops till the finish. WE start and stop all day and take much tighter turns at much slower speeds than any race car.
For daily stuff and around town the Effort needed to drive at slow speeds far outweighs the possible gains.
As a good friend of mine who is a Pro level Autocross driver says: "F*ck that, the effort just ain't worth it..."
BTW even though the Power steering belt is Not connected for the REALTIME ITR cars, they still run the system full of fluid just to make weight, It actually balances the car with weight distribution AND if they ever needed to run the Powersteering then it is readily available.
Removing the belt is one thing,,, Try it to see if you can handle the extra effort all the time. Removing the WHOLE power steering is somethng completely different.
Good luck,
A.