I have some guinea pig questions...?

First the pros and cons of c and c cages. Also, do you put cubes under the chloroplast? and I was wondering what your thoughts were on fleece bedding, from an experienced user. How much food should I give a pair of guinea pigs a day, and how long will a bag of food usually last? And how often do i wash them? (I know they must be very comfortable with me first)