Never feed to grow. Feed to nourish. Powerfeeding can have detrimental impact on a snakes health and lifespan. That being said, 1 large mouse every 10 days is more ummm nutrition for lack of a better word, than 1 medium every 7 days. But again, you should be feeding prey items sized according to the weight and girth of your snake, and frequency of feeding should really be based on age and size of your snake. They will grow when and how they want to, all snakes are different.