If your little one is doing well on RC and it is not presenting any issues then that is great! If you are determined to try other brands, I would suggest looking at the sticky in the Health and Diet section. It has a list of some of the more recommended (YT member recommended in any case) brands of food.
You may also want to try this site:
Dog Food Review Ratings
It will link you to several sites that examine commercial brands, home cooking, raw feeding, supplements, etc.
Keep in mind that what is best for one person's dog may not be best for YOUR dog. Do some trial and run test with feeding different brands to your little one and examine the results. Be sure when you switch foods to do it gradually to avoid digestional issues, rather than all at once.