Royal Canin is just an "OK" food. There definitely are better (and FAR WORSE!) foods out there
I would use those sites above, you want your chis on a 4, 5 or 6 star food. Most kibbles are produced by huge companies. This is hard for me to trust. So instead I generally recommend one of the two "privately owned" kibble companies still out there--Fromm Family Foods (Four Star Nutritionals line is their premium product), and Champion foods (Orijen, Acana). There are also other options -- like pre-made raw products. These are 100% better than kibble any which way you take them because they are less processed. There are dry/dehydrated products like Ziwipeak (kinda expensive IMO), and The Honest Kitchen, or there are fresher/frozen options available at some premium pet boutiques such as Nature's Variety or Stella & Chewy's. We love Stella & Chewy's here, they are a favorite!