Is cheap milk good for baby?

Hi Mummies, do any of you give GROW's formula milk to your baby? Is it fine to give baby a formula milk that is that cheap? It costs almost $19 only for infant-12 months. I have been using it as I changed from s26 to Grow but not really sure if its fine as im a ftm. I changed his milk formula as he kept asking for it every 2 hours even when he is already 2 months. Now he is 3 months plus and i have been giving him Grow Formula. He is a c section baby, but I really dont know which formula I should stick to as I know we cant keep on changing. Is Aptamil a good formula? As I'm planning to change just not sure which.