How many people go by the 10% of the body weight to determine the size of the feeder.

I am currently debating this - I fed my 1,600 gram boa an 80 gram rat the other night but he never seems satisfied. When I did the math on the 10% of body weight it seemed like a huge rat was in order.

What do you all suggest.

I've been feeding once every two weeks currently. He is about 2.5 or 3 years old.

Thanks